Another solution to this situation is to squash your changes in place so that your branch is just 1 commit, and then do the rebase against your master branch or equivalent.
Works great if you’re willing to lose the commit history on your branch, which obviously isn’t always the case.
I really enjoyed my time with it, even though I’ve not played many games in this “style”.
The campaign is quite lengthy even though it’s not finished yet, so you’ll definitely get your money’s worth.