We’ve created the 1.1 release branch, releases/FreeCAD-1-1, in the git repo (yes, this means that the 1.1 release will be coming Real Soon Now, for some definitions of “soon” 
). If you are developing a patch that only applies to 1.1, and should not be included in main, you can make PRs against that branch. All other PRs (that is, about 99% of them) should continue to be made against main. Maintainers will take care of ensuring that PRs that are appropriate for both branches make it onto both, developers don’t need to do anything special to make that happen.
Regarding the release of 1.1 – we need to do some test runs of the release build process, as usual. We’ll release these for public testing as “release candidates” labelled RC1, RC2, etc. The final release of 1.1.0 will be made once there are zero remaining blockers. Don’t forget there’s a bug bounty program!!