Back Court Violation Situation

[Huntin' Ref]

I am not sure if I kicked this call or not so I'd like your input.

A1 has the ball in his back court and passes to A2 (this is not a throw-in). B1 while sprinting lunges and steals the pass. His fist foot lands in his (B's) front court and the second foot lands in the back court. The thing is, he wasn't "jumping" in my opinion. It was elongated steps lunging for the ball (which could be argued as well). This could be deemed splitting hairs. I called the BC violation, knowing the rule, but my definition of "jump" and the coaches weren't the same....... Thoughts?

Here is the rule:
ART. 3
During a jump ball, throw-in or while on defense, a player may legally jump from his/her frontcourt, secure control of the ball with both feet off the floor and return to the floor with one or both feet in the backcourt. The player may make a normal landing and it makes no difference whether the first foot down is in the frontcourt or backcourt.