When is Draw Their Fire used, can it be decided after seeing the crit card, and can it be used more than once?

Question

Accepted Answer

Decide before the damage card is drawn: Draw Their Fire triggers after cancelling, when uncancelled hits remain, and the critical result (not the already-revealed card) is what moves, so you can't see the card first. It absorbs one critical per attack. It never stops the original target being hit.

Star Wars: X-Wing Miniatures Game

When is Draw Their Fire used, can it be decided after seeing the crit card, and can it be used more than once?