[greymule]

Somewhere in the umpire manual or the case book or the rules supplement is an admonition that the LBR is not in effect when F1 in the circle acts as a cutoff. The governing principle might be as follows: "With a play in progress, the LBR does not necessarily go into effect the instant F1 gets the ball in the circle. Depending on the type of play, use your judgment to give the runners a little time to make the transition from ball in play to ball in the circle."

The OP is a HTBT, but unfortunately, the call was apparently correct. I think that the LBR has outlived whatever usefulness it had, especially at the higher levels.