Submodule "git branch" says (HEAD detached at <incorrect-commit>)

Greetings,

I have a repo with two branches A and B, say, and a submodule pointing to a repo also with two branches, say C and D. Branch A of the parent uses branch C of the submodule, while B uses D. My clone is in a state (that I've seen often) where branch A's submodule directory _appears_ to be using a commit for D when really it's a commit for C. "git branch" in the the submodule directory says "(detached from <commit-for-D>)" but this seems to be wrong. I did "git diff <commit>" in the submodule directory to show that it was the C-commit and not the D-commit as it appeared. Could "git branch" in the submodule directory be referring to the commit at the time it was first detached and not updating after a "git submodule update --init" in the parent?

Thanks,
- Julius