mythtv compatibility between stable, testing, and unstable

Newer releases of MythTV are often not compatible with older releases,
due to changes in the database structure (I think). Christian, do you
always build the same version of MythTV for stable, testing, and
unstable? In other words: can I have a backend that runs stable, have a
frontend that runs either testing or unstable, and be sure that my
frontend and backend will always be compatible with each other?

Thanks for all your great work!

-Rob