Assignment "Copy the default branch only" setting not working

I've created 3 assignments over the past week, each from a repository that has two branches. Even though I've checked the "Copy the default branch only" setting, the resultant starter code repository has contained both of the original branches. In one case, "main" was not preserved as the default branch. This seems like a pretty big problem if, for example, one of the branches is a solution branch.

I've tried going to the starter code repository and deleting the extra branches, before distributing the assignment, and that seems to be a workaround for now. Needless to say, it would be nice not to need that extra step 🙂

Edit: I got here by googling "github classroom issues" but I now wonder if that was a mistake: where is the correct place to go to report issues with the github classroom website, not necessarily the cli tool?