I thought anti-air command grabs hit while the opponent was on their way up?
What MysteriousJ said, if you block his j.hp in the air you'll land before him and be able to punish him before he's able to block.
Er... No it's not. <_<
Excelebella is unblockable against any character that is moving upwards faster than x pixels per frame. It doesn't just apply to jumps. It applies to everything that makes your character move fast enough going upwards, even if the character can technically still block. It has nothing to do with pre jump frames or landing frames.
I've blocked it while moving upward. But I can't remember how/the setup. I don't remember the pixels per frame being "any" movement. If it indeed is (and I won't argue that it isn't since I really can't be bothered to search out the change log) but if it is supposed to be that way, then what I've experienced in the past must be a bug.
Whenever it's not a low or projectile.
You don't need a setup, your upward movement slows down when you jump, gravity works like that.