So Chun’s current B&B is (j.RH) 4MK, MK, j.RH, RH, Hozanshu. It does 349 damage.
If instead you do (j.RH) 4MK, MK, j.RH, RH, 3X j.2MK . It does 374 damage.
Both combos end in knockdown, and work against the entire cast anywhere on the screen.
The trick that may give some of you trouble is that you need to hit the opponent much earlier in the air with the j.RH then you would with what is considered the current standard B&B.
On some characters your j.2MKs may look like there is no way in hell they will hit and appear almost as chun is stomping on air verse some characters, but it will indeed connect all three giving you a knockdown.
EDIT: The current B&B only has 1 gap you can really fill in to add on more damage (after the jump in go into RH, EX-FB before continuing on with the 4MK, MK)
This new B&B actually has the same above but when you’re in the corner you can tag on an EX-SBK for more damage before the RH, 3xheadstomps