Sub allowed before clock starts?

[Scrapper1]

We've also hashed this question around quite a bit. Team A is down to only 6 players. A6 replaces A1. Before the clock starts, A6 turns an ankle and is unable to continue, even after Team A takes a time-out. Can A1 return to the game.

Seems like the answer is now a definitive "yes". 8.2 Situation B addresses it almost directly, although it deals with a free throw action. But a player who just came out of the game is allowed back in to replace an injured player, even though the clock didn't start.

Can you tell I'm having fun going through my new casebook?