Backcourt violation or not?

[BktBallRef]

A2 was in the backcourt and landed straddling the midcourt line?
If he jumps from the BC, catches the ball and lands with his FC foot first and then with the BC, violation. BC first, then FC, no violation because he never has FC status.

A2 was straddling the midcourt line, jumped to receive ball and landed straddling the midcourt line?
This play is no different than the first one. Whether straddling the line or standing in the BC, the player has BC status. You need to understand that to rule on these plays.

A2 was in the frontcourt and landed straddling the midcourt line?
BC violation.

Are there different answers for each of these situations where A2 receives the pass from A1 who is in the backcourt and subsequently passes to A3 who is in the backcourt?
No. That's only an issue if A2 passes the ball while airborne from the FC.