"T" is the first day. T is the trade date that closes above the short sellers margin call price. "T+1" is the second day "T+2" is the third day "T+3" is the fourth and final day.
The CLOSING price is what matters!!
If on any of the days the short sellers manage to knock the price down below their margin call price and close at that price, then they reset the days. Hence, I hope that some longs do sell on the earlier days only at fairly high prices so a reset doesn't occur. If some longs in Canada can buy on days that are not T+3 near the close, then that's helpful. The backstop should insure you're getting a good deal on those buys. As for your other arguments I direct you again to these two links:
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