After searching for a long time (without a search function, I might add
), I discovered that the thread where this was discussed at length was deleted.
My opinion is that you blow the play dead as soon as it is caught inbounds, remove 0.3 seconds from the time that remained at the beginning of the play, and put the ball back in play at the spot closest to where it was when you blew the whistle.
I could easily be persuaded to take a full second off the game clock (accounting for lag time). I think the "do-over" approach is incorrect for a sanctioned HS or NCAA game. Although, as somebody else pointed out, this was summer league, so it doesn't matter too much, as long as everybody can live with it. As always, just my opinion.