This is a bug. It has already been reported multiple times on the bug reporting thread and the devs have already confirmed to be working on a solution.
Blocking inputs become inverted on cross-up and trying to dash under the oponent will never result in a backdash on specific timing, no matter the inputs
Bugs happen often, even if you bring in “real coders” (whatever that means).
This bug really sucks, though. I’m sad it hasn’t been fixed yet. It is definitely serious enough to temporarily put the game away until it’s fixed.
I asked the team about it, and they said they were going to fix “some bugs” before patch 3.5 (presumably, this one would be included in that), but they weren’t able to give a timetable for it. So the best we can do is wait, I guess.
I have wanted to start playing KI seriously again after this patch, but the bugs in it have discouraged me heavily.
I have not touched the game since 3.4 came out because every time i thought about playing i remembered the system issues and 2nd guessed myself.
I used to not understand why Pro players would leave this game, but now i get it. Things like this happen every single patch, and to be FORCED to deal with it for multiple months to make money must suck.
I cant bring myself to play the game for FUN anymore, so i cant imagine what it must be like to be “burned out” on Killer instinct and STILL have to put up with this stuff.