I would like to have a way to change the active blueprint with a signal. Ideally, a way to deploy the active blueprint and move to the next blueprint in a single tick.

If you want to loop through a blueprint book, you can do it by changing the construction robot signal. The active blueprint is only used as a fallback if you send a nonsense construction robot signal.

I am aware of that option, but with a few hundred blueprints in a book, it would be more comfortable to be able to change the active one. I already did create my own mod to place a sonstant combinator at the same location on every blueprint within the book with increasing con bot number, but I now have to port it from 0.17 to 1.1 and that is a bit of a hassle