a bavarois is a boiled custard with gelatin and whipped cream.
i've never tried freezing one. taking a hesitant guess, i'd say it might be doable. i wouldn't try freezing a regular custard, but i think that with the gelatin and whipped cream, it may be ok. cheescakes are commonly frozen, and i've had success freezing chocolate mousse before.
i don't know what kind of presentation you have in mind, but if you're feeling that you have to make it so far in advance that, because of time restraints, you need to freeze it, maybe you could line a springform pan with some cake or lady's fingers, set it in that, and serve it frozen in slices, maybe with a warm sabayon or something? that way you wouldn't have to worry about it possibly breaking when it thaws.
good luck and let us know how it comes out if you try.