Lane Violation or Not?

[djskinn]

Foul shot by A1, the attempt is obviously well short of the basket (airball). As the shot falls below the rim (but before it contacts the floor), B1 steps into the lane.

Is this a lane violation?

4.7.2 says "The ball becomes dead, or remains dead, when .. It is apparent the free throw will not be successful.

This was a game situation I had and called the violation. Neither coach protested the call and another foul shot was awarded.

However, was this the correct ruling?