The new 2,1 tech in a nutshell.
Once you start the 2,1 watch your opponent. If they jumped out of the string before it hit then complete the string with another 2. So on jump you 2,1,2 the last 2 takes you so far forward the opponent can not hit you with their cross up attempt.
2,1 on block should be ended with a cutter. You can follow up with lots of things but CD uses a lot of b1,2 to follow up
2,1 on hit confirm should be ended with ex fan dash cancel into combo of your choice.
There you go.