Correctable Error?

[dinoian]

I was working an intramural game earlier tonight when an interesting play came up that resulted from us working the game not being as alert as we should have. Here's what happened:

Players from team B are waiting at the scorer's table to enter the game when a whistle is blown for out of bounds, last touched by team B. At that whistle, some of the players from team B begin to walk off the court (as they are being substituted out) and the official awards the ball to team A without beckoning in the substitutes as the horn was never blown and they aren't aware that subs are set to enter. Team A inbounds the ball and hits a 3, while team A is expecting to be substituting, unaware that the ball is in play (players on sideline looking at lead official to beckon them in, but he never does, and players leaving the court looking at their bench, away from the play). Team B then calls a timeout and asks to correct it by allowing the subs and taking off the 3 points, returning the ball to team A. So my question is, is this a correctable error?

We did end up doing just that at the request/agreement of team B, but I'm curious as to what the proper procedure is for when the ball is awarded before substitutes have a chance to enter the game.