I don't know where you've seen it, but Luc says he likes to participate in each bounce, so he should have some sells there. It's true that it frees up the capital, but there aren't that many opportunities in position trading, I don't think it's a problem for him.
There is no set time, it can be fast, it can be a few days, or a week.
I don't think he has set percentages. He mentioned that he layers in the sells in profit, as well as sometimes leaving 20% of profits to run after the trade.