This situation is simply wrong. We've debated it here before and it is in direct contradiction with the rule....where team a must be the first
to touch after it goes into the back court and also the
last to touch before it went to the backcourt. The rule is quite clear and has been unchanged for decades. Nowhere in any rule does it say that it is a violation to cause the ball to have backcourt status.
Your examples show the absurdity of interpretation that sit. #10 suggests.
Furthermore, consider this additional case (inspired by yours):
4. A1, dribbling in the backcourt near the division line is guarded by B1 who is completely in frontcourt. B1 reaches and touches the ball between dribbles (ball on the way back up ) but not enough to prevent A1 from continuing the dribble. A1 continues to dribble (while still in the backcourt). Violation???
When B1 touched the ball it gains FC status. When A1 again touches the ball on the next dribble, it gained BC status. To be consistent with situation 10, this would have to be a violation on A1 since A1 caused the ball to have BC status.
Does ANYONE here think that this is REALLY what is intended? That B1 could force a turnover by merely touching the ball from across the division line while A1 is dribbling it??? That is what situation 10 implies. Again, situation 10 is simply wrong.
I expect a correction to come on on this situation. It may not come this year...but it will come.