Incremental backups with git bundle, for all branches

Question

What is the easiest way to do incremental backups of a git repository with git bundle?

If I just wanted to backup a single branch, I could do something

Answer 1

Seems opqdonut solution will not work, cause ^backup/A ^backup/B only points to last incremental backup. And actually need to exclude refs from all previous incremental backups.

Need to create remotes for each of previous bundles.

UPD: No, it should work, see Jukka comment below.