Coach ejection (Basketball - LHSAA)

[Real Deal]

From my understanding - You report to the official book about the second technical, tell them to write down the time, quarter and score - then step back and say put 1 minute n the clock for the coach to leave the area. If they don't leave when the buzzer hits zero then the game is forfeited. Now the unwritten rule - I've been told one minute for years but can't find any time or timeline for a coach to be removed in any book. If there isn't a 'written' rule then how can we enforce when Coach Johnny gets tossed? How long do we give them?