DoH: Why server-list with ips as well as uri?

[RickardCardell]

Hi
This is a great app :) I just have a small question:
Why is there both a list of ip:s as well as the Server URL in the Dns-Over-Https configuration in the app?

[RickardCardell]

I found a good video that might have answered my question.
The list of ip:s are optional which I didn't understand by looking at the docs.
However, I assume that if the ip:s are entered, there is no need to make a dns-lookup for the DoH server-url itself?