Game Manager - foundry versions, mods and games

I have a game that runs on v9 and I created a copy that I enabled v11 on, to mess around and whether it’s time to make a switch. Neat.

The problem:
When I wanted to upgrade mods in the bazaaz it said that I need to switch my overall account foundry version. I can do it. But what will happen with my v9 versions of the mods? Will they get upgraded to v11 and break my v9 worlds?

Yes. You need to upgrade and downgrade the modules between switching worlds back and forth.

For testing purposes I’d suggest using a local instance of foundry on v11 instead, until you are ready to make the jump.

As I suspected. Thank you for your help