Is there any use for a bite/stone edge Tyranitar
Assuming you plan to evolve and power up several smack down Tyranitar during community days and you have 30 plus charge TMs?
I agree that no decisions should be made before the community day is over. There's very rarely any reason to commit resources in advance.
However, it's extremely unlikely that SD Tyranitar isn't the absolute nuts as a rock attacker. GPs own article on the CD has the numbers for SD being a copy of any fast move and any nerf would have to be huge to prevent it from dethroning Golem. Even if SD ends up being kind of a meh fast move, TTar will be rock king with it.
If you do not have a lot of charge TMs, then Bite/Stone Edge can still be used as a rock attacker if during community day you don't evolve enough with Smack Down/Stone Edge and get several with SD/Crunch or SD/Fire Blast.
If do have charge TMs to spare, then in addition to changing all your CD Tyranitars to Stone Edge, you can change your old B/SE to B/C.
If you have maxed teams of six Tyranitar with B/S and six with B/C... why?
I agree that SD / SE Ttar should be a beast and that the nerf would need to be massive to prevent this. However, this might not be initially obvious if they tweak Smackdown to be a weak move with high energy gain (similar to the psychic move Psycho Cut which has a mere attack factor of 5 but to many is preferred over Confusion with attack factor of 20). That would still be good, but I think many are hoping it will be a quick AND powerful move ... but that might be simply too much to ask for.