First of all - I am very excited about the Github integration.
One thing I noticed when testing it is that the Github base branch was not the anvil master branch.
In my case it was ironically the hotfix branch 
No really an issue but might be confusing for some people.
Thanks for spotting this! It turns out to be tricky to fix, because Github doesn’t let us set a default branch on the initial empty repository, it can only be set after the first push, and that push is queued up asynchronously after we create the repo, to avoid blocking your work while it happens.
We’re working on it! In the meantime, you can absolutely update the default branch manually - Anvil won’t overwrite your changes.
