Confusing mismatch between official upgrade guide and docs guide re: custom routes

[HerrBertling]

Hey 👋

I'm going through the official upgrade guide to plan the migration within some tickets for our SPA.

Of course (😬), I've mistakenly used the guide from the docs first and then noticed that I should use the incremental upgrade one linked above.

While rewriting the tickets, I noticed that the docs guide speaks about refactoring custom routes – which we do have and surely need to refactor. This step is missing in the official migration guide.

I'm well aware that we need to do this anyway. I was just wondering: Shouldn't this step be mentioned in the incremental migration guide as well?