fix(schedule10): apply the Story 11.3 code review findings

Adversarial code review of Story 11.3 raised 31 findings (6 high, 16 medium,
9 low). Six needed a product call and were decided by Scho; the other 25 were
patched. All 30 resulting patches are here.

Behavioural fixes:

- The "unsaved data will be lost" confirmation on Enter Road Data navigated
  without discarding the edit. Returning via Back reopened the panel still
  holding it, and Save then wrote it against a freshly re-read revisionCount,
  so the lock passed and data the user was told was discarded persisted.
- A stored supply block absent from the CATALOGUE rendered blank: the option
  list was built by filtering the served list, so a code that is not a row
  yielded nothing. ab7dea8 fixed only the in-catalogue case.
- Any TSA interaction dropped a cross-TSA supply block. The clear was gated on
  the prefix not matching, with no check that the TSA had changed, so
  re-selecting the SAME TSA cleared it; and clearing the control left an
  orphan block, since startsWith('') is always true.
- Check Status discarded road attribution. The backend prefixes roadName and
  subzone with the page label only, so on a multi-road page the flattened line
  could not say which road failed; the roadDetailLabel is now prefixed.
- Read-only REMOVED Save from the DOM, contradicting AC11 and deviation 7,
  which both require every write control rendered and disabled. The test that
  codified the removal was flipped.
- A null revisionCount made Save a silent no-op with no banner at all.
- Ballast method N/D coercion is now mirrored in the form and the request body
  (material forced to NA, and on N the dimensions, actualCost and otherTransfer
  zeroed but ttTransfer kept, per the server's own asymmetry).
- Road Group is blanked when the location is edited rather than showing a value
  the server derived from the location as stored.
- The TFL advisory was unreachable behind maxLength={2} while a blank TFL was
  ungated; the comments byte cap used 3500 where the column allows 4000, so a
  legal save was blocked; an over-length road name returned the off-list
  message instead of the server's; a de-listed BEC rendered its raw catalogue
  id; five derived money cells inverted the legacy masks; a page edit did not
  clear a stale check-status result; the ballast material hint fired before any
  method was chosen; and leaving the road level stranded an open delete
  confirmation whose Yes then did nothing.

Shared components, additively and with no change for other schedules:

- CodeComboBox gains an opt-in matchMode prop defaulting to today's substring
  match, so Schedules 2, 4 and 8 filter exactly as before. Schedule 10's BEC
  Zone opts into prefix, which is what AC5 specifies.
- number.ts gains fmtWholeCost, the mask.int.7digits (#,###,##0) formatter the
  derived integer totals needed.

Test coverage:

- millId and year were asserted on 2 of 9 endpoints. MSW matches a path
  regardless of query string, so dropping the query passed every test and would
  have 400'd every write in production. All 9 are now pinned.
- The two new backend code lists shipped with zero coverage: deleting either
  @query body, or swapping the two toCodes(...) arguments in the assembler,
  left the suite green. Both lists are now pinned, including a transposition
  guard.
- Writing that coverage showed the referenced-union leg on both queries had no
  coverage AND COULD NOT BE GIVEN ANY as seeded. It reads
  "WHERE <date window> OR code IN (<referenced>)", so it can only rescue a code
  that HAS a row and fell outside the window; V20260819 deliberately left 16Z
  out of its code table on the stated grounds that this kept it representative
  of the rows motivating that leg, which is backwards. 16Z is now seeded
  EXPIRED and referenced by page 8904, making the leg falsifiable in both
  directions. 99A stays absent to pin the boundary that justifies synthesising
  a stored code client-side.
- Road-detail delete had no test at all. Three vacuous assertions were
  replaced. Range constants were pinned at one bound only, and stSurfaceWidth,
  ROAD_NAME_MAX and TFL_MAX were untested entirely.
- AC14's nav-position and not-admin-only halves were unasserted, and AC15's
  accessibility assertions were never written. Both are covered now.
- A source-level tripwire guards the shared ComboBox rule in _overrides.scss.
  jsdom does not apply the SCSS, so no rendering test can observe the computed
  height; this is a tripwire, not a behaviour test.

Verified: frontend 165 Schedule 10 tests green, full suite 979/980 with the one
failure pre-existing (Schedule8 Helicopter, passes 86/86 in isolation); backend
262 unit and 87 integration tests green; lint and Prettier clean.

NOT verified in a browser -- that belongs to Story 11.4 with the axe sweep.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Author: Rylan-cgi

backend/src/test/java/ca/bc/gov/nrs/ilcr/schedule10/Schedule10DocumentIT.java

@@ -1,5 +1,6 @@
 package ca.bc.gov.nrs.ilcr.schedule10;
 
+import static org.hamcrest.Matchers.contains;
 import static org.hamcrest.Matchers.hasItem;
 import static org.hamcrest.Matchers.hasSize;
 import static org.hamcrest.Matchers.is;
@@ -329,6 +330,76 @@ void codeLists_areYearFilteredAndOmitRemovedFields() throws Exception {
         .andExpect(jsonPath("$.codeLists.soilMoistureCodes").doesNotExist());
   }
 
+  @Test
+  @DisplayName("the TSA and supply-block lists are served, year-filtered, and not transposed")
+  void tsaAndSupplyBlockLists_areServedAndYearFiltered() throws Exception {
+    // Both lists shipped with NO coverage at all: deleting either @Query body, or swapping the two
+    // toCodes(...) arguments in the assembler -- they are both List<CodeDescriptionDto>, so it
+    // compiles -- left the suite green. Each assertion below fails under one of those mutations.
+    mockMvc.perform(get(ENDPOINT).param("millId", "710").param("year", "2021")
+            .accept(MediaType.APPLICATION_JSON))
+        .andExpect(status().isOk())
+        // Present and populated, so deleting a @Query body reds this.
+        .andExpect(jsonPath("$.codeLists.tsaNumbers").isArray())
+        .andExpect(jsonPath("$.codeLists.supplyBlocks").isArray())
+        .andExpect(jsonPath("$.codeLists.tsaNumbers[?(@.code == '01')]", hasSize(1)))
+        .andExpect(jsonPath("$.codeLists.tsaNumbers[?(@.code == '16')]", hasSize(1)))
+        .andExpect(jsonPath("$.codeLists.supplyBlocks[?(@.code == '01A')]", hasSize(1)))
+        .andExpect(jsonPath("$.codeLists.supplyBlocks[?(@.code == '16G')]", hasSize(1)))
+        // The descriptions are what the control DISPLAYS, so they are part of the contract.
+        .andExpect(jsonPath("$.codeLists.tsaNumbers[?(@.code == '01')].description",
+            contains("Arrow TSA")))
+        .andExpect(jsonPath("$.codeLists.supplyBlocks[?(@.code == '01A')].description",
+            contains("Arrow TSA Block A")))
+        // TRANSPOSITION GUARD: a TSA code must never appear in the block list, or the reverse. A
+        // swap of the two assembler arguments compiles and is caught only here.
+        .andExpect(jsonPath("$.codeLists.tsaNumbers[?(@.code == '01A')]", hasSize(0)))
+        .andExpect(jsonPath("$.codeLists.tsaNumbers[?(@.code == '16G')]", hasSize(0)))
+        .andExpect(jsonPath("$.codeLists.supplyBlocks[?(@.code == '01')]", hasSize(0)))
+        .andExpect(jsonPath("$.codeLists.supplyBlocks[?(@.code == '16')]", hasSize(0)))
+        // V20260819 seeds '90','Retired TSA' expiring 2010-12-31 stating it exists "to pin that the
+        // year filter drops a code". Nothing pinned it until now: no stored 2021 page references
+        // '90', so neither leg of the predicate can rescue it.
+        .andExpect(jsonPath("$.codeLists.tsaNumbers[?(@.code == '90')]", hasSize(0)));
+  }
+
+  @Test
+  @DisplayName("an expired block a stored page references is rescued by the referenced-union leg")
+  void supplyBlocks_referencedUnionRescuesAnExpiredCode() throws Exception {
+    // The union leg on both queries had NO coverage: it can only rescue a code that HAS a row and
+    // fell outside the date window, and no fixture created that shape until V20260819 was corrected
+    // to seed '16Z' expired (see that file's CORRECTED note). Page 8904 references it, on mill 712.
+    mockMvc.perform(get(ENDPOINT).param("millId", "712").param("year", "2021")
+            .accept(MediaType.APPLICATION_JSON))
+        .andExpect(status().isOk())
+        // Drop the `OR TSB_NUMBER_CODE IN (...)` leg and this goes to 0.
+        .andExpect(jsonPath("$.codeLists.supplyBlocks[?(@.code == '16Z')]", hasSize(1)));
+
+    // Scoped to the MILL and the YEAR: mill 710 references no such block, so the expired code stays
+    // dropped there. Remove the date predicate and this goes to 1.
+    mockMvc.perform(get(ENDPOINT).param("millId", "710").param("year", "2021")
+            .accept(MediaType.APPLICATION_JSON))
+        .andExpect(status().isOk())
+        .andExpect(jsonPath("$.codeLists.supplyBlocks[?(@.code == '16Z')]", hasSize(0)));
+  }
+
+  @Test
+  @DisplayName("a code absent from its table entirely is not served, however many pages reference it")
+  void codeLists_cannotServeACodeWithNoRow() throws Exception {
+    // Page 8903 (mill 712) stores TSA '99' / TSB '99A', neither of which has a row in its code table.
+    // The union leg selects FROM the code table, so it cannot invent one. This is the contract
+    // boundary that makes the FRONTEND synthesise a stored code as its own option (review H2) — pinned
+    // here so nobody "fixes" the client by pointing at a backend guarantee that does not exist.
+    mockMvc.perform(get(ENDPOINT).param("millId", "712").param("year", "2021")
+            .accept(MediaType.APPLICATION_JSON))
+        .andExpect(status().isOk())
+        .andExpect(jsonPath("$.codeLists.tsaNumbers[?(@.code == '99')]", hasSize(0)))
+        .andExpect(jsonPath("$.codeLists.supplyBlocks[?(@.code == '99A')]", hasSize(0)))
+        // The page itself still lists, carrying its stored location verbatim.
+        .andExpect(jsonPath("$.pages[?(@.pageId == 8903)].tsaNumber", contains("99")))
+        .andExpect(jsonPath("$.pages[?(@.pageId == 8903)].tsbNumberCode", contains("99A")));
+  }
+
   @Test
   @DisplayName("BEC is served structurally, gated by the surviving BR-06 xref (deviation (e))")
   void becIsStructuralAndXrefGated() throws Exception {

backend/src/test/resources/db/V20260819__tsa_tsb_code_table_dates_and_seeds.sql

@@ -26,9 +26,20 @@ ALTER TABLE THE.TSB_NUMBER_CODE ADD (
 -- The TSA numbers and supply blocks the Schedule 10 read fixtures store on their pages, so each
 -- stored location resolves to an option in its own dropdown.
 --
--- '99'/'99A' and '16Z' are deliberately NOT seeded: they are the unmapped-TSA and no-TSB-branch
--- fixtures, and leaving them out of the code tables keeps them representative of the legacy rows
--- that motivated the referenced-union leg on every list.
+-- '99'/'99A' are deliberately NOT seeded: they are the unmapped-TSA fixtures, and a code with no row
+-- at all is a real delivery state the dropdown has to survive.
+--
+-- CORRECTED 2026-08-20 (code review H5): this block previously left '16Z' unseeded too, on the stated
+-- grounds that doing so kept it "representative of the legacy rows that motivated the referenced-union
+-- leg". That is backwards. The union leg reads
+--   SELECT ... FROM THE.TSB_NUMBER_CODE WHERE <date window> OR TSB_NUMBER_CODE IN (<referenced>)
+-- so it can only rescue a code that HAS a row and fell outside the date window. A code absent from the
+-- table can never be selected by it, however many pages reference it — so the unseeded fixtures
+-- exercised nothing, and the leg had no coverage on either list. '16Z' is now seeded EXPIRED and is
+-- referenced by page 8904 (mill 712), which is the one shape that does exercise it.
+--
+-- A code that is absent ENTIRELY still cannot be served, which is why the FRONTEND synthesises the
+-- stored code as its own option (review H2) rather than relying on the backend for it.
 INSERT INTO THE.TSA_NUMBER_CODE (TSA_NUMBER, DESCRIPTION, EFFECTIVE_DATE, EXPIRY_DATE, UPDATE_TIMESTAMP)
   VALUES ('01', 'Arrow TSA', DATE '1900-01-01', DATE '9999-12-31', SYSDATE);
 INSERT INTO THE.TSA_NUMBER_CODE (TSA_NUMBER, DESCRIPTION, EFFECTIVE_DATE, EXPIRY_DATE, UPDATE_TIMESTAMP)
@@ -42,3 +53,9 @@ INSERT INTO THE.TSB_NUMBER_CODE (TSB_NUMBER_CODE, DESCRIPTION, EFFECTIVE_DATE, E
   VALUES ('01A', 'Arrow TSA Block A', DATE '1900-01-01', DATE '9999-12-31', SYSDATE);
 INSERT INTO THE.TSB_NUMBER_CODE (TSB_NUMBER_CODE, DESCRIPTION, EFFECTIVE_DATE, EXPIRY_DATE, UPDATE_TIMESTAMP)
   VALUES ('16G', 'Lakes TSA Block G', DATE '1900-01-01', DATE '9999-12-31', SYSDATE);
+
+-- An EXPIRED block that page 8904 (mill 712) still references: the only fixture that makes the
+-- referenced-union leg falsifiable. Out of the date window, so the date predicate alone drops it; in
+-- the referenced set for mill 712, so the union leg brings it back for that mill and no other.
+INSERT INTO THE.TSB_NUMBER_CODE (TSB_NUMBER_CODE, DESCRIPTION, EFFECTIVE_DATE, EXPIRY_DATE, UPDATE_TIMESTAMP)
+  VALUES ('16Z', 'Lakes TSA Block Z (retired)', DATE '1900-01-01', DATE '2010-12-31', SYSDATE);

frontend/src/components/core/CodeComboBox.tsx

@@ -7,6 +7,16 @@ export interface ComboOption {
   readonly description: string
 }
 
+/**
+ * How typed text is matched against an option's description.
+ *
+ * `substring` is the historical behaviour every caller had before this prop existed and stays the
+ * default, so Schedules 2, 4 and 8 filter exactly as they always have. `prefix` is opt-in for the
+ * controls whose AC specifies it — Schedule 10's BEC Zone (AC5), where typing `SBS` must offer the
+ * `SBS*` zones and not every zone containing those letters.
+ */
+export type ComboMatchMode = 'substring' | 'prefix'
+
 interface CodeComboBoxProps {
   id: string
   titleText: string
@@ -16,6 +26,8 @@ interface CodeComboBoxProps {
   selectedCode: string
   /** Called with the chosen option's code ('' when cleared). */
   onSelect: (code: string) => void
+  /** Defaults to `substring`, the behaviour every pre-existing caller relies on. */
+  matchMode?: ComboMatchMode
   disabled?: boolean
   invalid?: boolean
   invalidText?: string
@@ -34,12 +46,18 @@ const CodeComboBox: FC<CodeComboBoxProps> = ({
   items,
   selectedCode,
   onSelect,
+  matchMode = 'substring',
   disabled,
   invalid,
   invalidText,
   className,
 }) => {
   const selectedItem = items.find((option) => option.code === selectedCode) ?? null
+  const matches = (description: string, typed: string): boolean => {
+    const haystack = description.toLowerCase()
+    const needle = typed.toLowerCase()
+    return matchMode === 'prefix' ? haystack.startsWith(needle) : haystack.includes(needle)
+  }
   return (
     <ComboBox<ComboOption>
       id={id}
@@ -49,14 +67,15 @@ const CodeComboBox: FC<CodeComboBoxProps> = ({
       items={items}
       itemToString={(item) => item?.description ?? ''}
       selectedItem={selectedItem}
-      // Autocomplete: typing filters the list by a case-insensitive match on the description. Show the
-      // whole list when nothing is typed OR when the input still equals the current selection (menu
-      // just opened) — otherwise a selected value would filter the list down to itself and hide the
-      // other options. Explicit so filtering doesn't depend on the Carbon default.
+      // Autocomplete: typing filters the list by a case-insensitive match on the description, of the
+      // kind `matchMode` names. Show the whole list when nothing is typed OR when the input still
+      // equals the current selection (menu just opened) — otherwise a selected value would filter the
+      // list down to itself and hide the other options. Explicit so filtering doesn't depend on the
+      // Carbon default.
       shouldFilterItem={({ item, inputValue }) =>
         !inputValue ||
         inputValue === selectedItem?.description ||
-        (item?.description ?? '').toLowerCase().includes(inputValue.toLowerCase())
+        matches(item?.description ?? '', inputValue)
       }
       disabled={disabled}
       invalid={invalid}

frontend/src/components/schedule10/RoadDetailFields.tsx

@@ -2,13 +2,16 @@ import type { FC, ReactNode } from 'react'
 import { Select, SelectItem, TextArea, TextInput } from '@carbon/react'
 import type { CodeDescription, Schedule10CodeLists } from '@/interfaces/Schedule10Response'
 import CodeComboBox from '@/components/core/CodeComboBox'
+import type { ComboMatchMode } from '@/components/core/CodeComboBox'
 import CommaNumberInput from '@/components/core/CommaNumberInput'
-import { fmtCurrency, fmtNumber } from '@/utils/number'
+import { fmtCurrency, fmtWholeCost } from '@/utils/number'
 import type { MaskedField, RoadDetailErrors, RoadDetailFormValues } from './validation'
 import {
   COMMENTS_MAX,
   ROAD_NAME_MAX,
+  ballastForcesMaterialNa,
   ballastMaterialRequired,
+  ballastZeroesFigures,
   previewCostPerVolumePerLength,
   previewMaterialTotal,
   previewStabilizingCostPerLength,
@@ -70,15 +73,20 @@ const RoadDetailFields: FC<RoadDetailFieldsProps> = ({
   const id = (name: string) => `${idPrefix}-${name}`
 
   // A stored classification may have been de-listed since it was saved, in which case it is absent
-  // from the offerable list. Appending it keeps the field showing what the row actually holds
-  // instead of appearing unselected.
+  // from the offerable list. Appending it keeps the field showing what the row actually holds instead
+  // of appearing unselected — and it is appended with the row's OWN label, which the response carries
+  // on `becClassification` even for a de-listed value. Falling back to the catalogue id put a bare
+  // number where every other option reads `SBSmk1`.
   const becOptions: CodeDescription[] = codeLists.becClassifications.map((bec) => ({
     code: String(bec.biogeoclimaticCatalogueId),
     description: bec.label ?? String(bec.biogeoclimaticCatalogueId),
   }))
   const selectedBec = form.becbiogeoCatalogueId
   if (selectedBec !== '' && !becOptions.some((option) => option.code === selectedBec)) {
-    becOptions.push({ code: selectedBec, description: selectedBec })
+    becOptions.push({
+      code: selectedBec,
+      description: form.becbiogeoLabel === '' ? selectedBec : form.becbiogeoLabel,
+    })
   }
 
   const describe = (options: readonly CodeDescription[], code: string): string =>
@@ -136,6 +144,7 @@ const RoadDetailFields: FC<RoadDetailFieldsProps> = ({
     key: keyof RoadDetailFormValues,
     label: string,
     options: readonly CodeDescription[],
+    opts: { readonly matchMode?: ComboMatchMode; readonly disabled?: boolean } = {},
   ): ReactNode =>
     readOnly ? (
       readOnlyField(label, form[key] === '' ? '' : describe(options, form[key]))
@@ -146,14 +155,20 @@ const RoadDetailFields: FC<RoadDetailFieldsProps> = ({
           titleText={label}
           items={[...options]}
           selectedCode={form[key]}
-          disabled={disabled}
+          matchMode={opts.matchMode}
+          disabled={disabled || (opts.disabled ?? false)}
           invalid={Boolean(errors[key])}
           invalidText={errors[key]}
           onSelect={(code) => onChange(key, code)}
         />
       </Field>
     )
 
+  // `N` and `D` both have their material forced to `NA`; `N` additionally has its dimensions and two
+  // of its three costs zeroed, which `buildStabilizing` now sends rather than leaving to the server.
+  const materialForced = ballastForcesMaterialNa(form.stBallastMethodCode)
+  const figuresZeroed = ballastZeroesFigures(form.stBallastMethodCode)
+
   const endHaulRate = previewCostPerVolumePerLength(
     form.lessEndHaul,
     form.endHaulVolume,
@@ -173,7 +188,8 @@ const RoadDetailFields: FC<RoadDetailFieldsProps> = ({
           {combo('roadLifetimeCode', 'Road Type', codeLists.roadLifetimes)}
 
           <SubHeading>Moisture</SubHeading>
-          {combo('becbiogeoCatalogueId', 'BEC Zone', becOptions)}
+          {/* AC5: prefix match, not substring — typing `SBS` must not offer `ESSFmc`. */}
+          {combo('becbiogeoCatalogueId', 'BEC Zone', becOptions, { matchMode: 'prefix' })}
           {combo('relSoilMoistRgmClsCode', 'RSMR Class', codeLists.rsmrClasses)}
 
           <SubHeading>Shoulder</SubHeading>
@@ -196,28 +212,32 @@ const RoadDetailFields: FC<RoadDetailFieldsProps> = ({
           {numeric('sgActualCost', 'Sub-Grade Actual Cost', '$')}
           {numeric('sgTtTransfer', 'Sub-Grade TtT Transfer', '$')}
           {numeric('sgOtherTransfer', 'Sub-Grade Other Transfer', '$')}
-          <Derived label="Total Costs ($)" value={fmtCurrency(previewSubGradeTotalCosts(form))} />
+          <Derived label="Total Costs ($)" value={fmtWholeCost(previewSubGradeTotalCosts(form))} />
           {numeric('lessBridges', 'Less Bridges', '$')}
           {numeric('lessCulverts', 'Less Culverts', '$')}
           {numeric('lessLandings', 'Less Landings', '$')}
           {numeric('lessEndHaul', 'Less End Haul', '$')}
           {numeric('lessOverland', 'Less Overland', '$')}
           {numeric('lessOtherEng', 'Less OtherEng', '$')}
-          <Derived label="Total ($)" value={fmtCurrency(previewSubGradeTotal(form))} />
+          <Derived label="Total ($)" value={fmtWholeCost(previewSubGradeTotal(form))} />
           <Derived label="$/km" value={fmtCurrency(previewSubGradeCostPerLength(form))} />
         </Section>
 
         <Section heading="Additional Stabilizing">
           {combo('stBallastMethodCode', 'Ballast Method Code', codeLists.ballastMethods)}
           {numeric('stLength', 'Additional Stabilizing Length', 'km')}
           {numeric('stSurfaceWidth', 'Additional Stabilizing Surface Width', 'm')}
-          {combo('stBallastMaterialCode', 'Type', codeLists.ballastMaterials)}
+          {/* The server replaces the material with `NA` on both `N` and `D`, so offering a choice
+              here only invites one that will be discarded. */}
+          {combo('stBallastMaterialCode', 'Type', codeLists.ballastMaterials, {
+            disabled: materialForced,
+          })}
           {numeric('stDepth', 'Depth', 'm')}
           {numeric('stDistanceToSource', 'Distance to Source', 'km')}
           {numeric('stActualCost', 'Additional Stabilizing Actual Costs', '$')}
           {numeric('stTtTransfer', 'Additional Stabilizing TtT Transfer', '$')}
           {numeric('stOtherTransfer', 'Additional Stabilizing Other Transfer', '$')}
-          <Derived label="Total ($)" value={fmtCurrency(previewStabilizingTotal(form))} />
+          <Derived label="Total ($)" value={fmtWholeCost(previewStabilizingTotal(form))} />
           <Derived label="$/km" value={fmtCurrency(previewStabilizingCostPerLength(form))} />
         </Section>
       </div>
@@ -248,14 +268,14 @@ const RoadDetailFields: FC<RoadDetailFieldsProps> = ({
       <div className="schedule-10__fields">
         {numeric('endHaulDistance', 'End Haul Distance', 'km')}
         {numeric('endHaulVolume', 'End Haul Volume', 'm3')}
-        <Derived label="$/m3/km" value={fmtNumber(endHaulRate)} />
+        <Derived label="$/m3/km" value={fmtCurrency(endHaulRate)} />
       </div>
 
       <h4 className="schedule-10__detail-heading">Overland</h4>
       <div className="schedule-10__fields">
         {numeric('overlandDistance', 'Overland Distance', 'km')}
         {numeric('overlandVolume', 'Overland Volume', 'm3')}
-        <Derived label="$/m3/km" value={fmtNumber(overlandRate)} />
+        <Derived label="$/m3/km" value={fmtCurrency(overlandRate)} />
       </div>
 
       <div className="schedule-10__comments">
@@ -282,9 +302,19 @@ const RoadDetailFields: FC<RoadDetailFieldsProps> = ({
         )}
       </div>
 
-      {!readOnly && ballastMaterialRequired(form.stBallastMethodCode) && (
+      {/* Only once a method is actually chosen: a BLANK code lands in the `C` branch server-side, so
+          `ballastMaterialRequired('')` is true and the hint fired on every untouched new road. */}
+      {!readOnly &&
+        form.stBallastMethodCode.trim() !== '' &&
+        ballastMaterialRequired(form.stBallastMethodCode) && (
+          <p className="schedule-10__hint">
+            A material Type is required for this Additional Stabilizing code.
+          </p>
+        )}
+      {!readOnly && figuresZeroed && (
         <p className="schedule-10__hint">
-          A material Type is required for this Additional Stabilizing code.
+          This Additional Stabilizing code stores its dimensions, actual cost and other transfer as
+          zero.
         </p>
       )}
     </div>

frontend/src/components/schedule10/RoadDetailPage.tsx

@@ -153,11 +153,10 @@ const RoadDetailPage: FC<RoadDetailPageProps> = ({
               onMask={onMask}
             />
             <div className="schedule-10__panel-actions">
-              {!readOnly && (
-                <Button kind="primary" disabled={controlsDisabled} onClick={onSave}>
-                  Save
-                </Button>
-              )}
+              {/* AC11 and deviation 7: rendered and disabled outside Draft, never removed. */}
+              <Button kind="primary" disabled={controlsDisabled || readOnly} onClick={onSave}>
+                Save
+              </Button>
               <Button kind="secondary" onClick={onCloseForm}>
                 Close
               </Button>