AA also charges a fee for "last minute" awards, which is pure extortion - anything less than three weeks costs $50, or $75 for same day ticketing. Yet they do the exact same work two days in advance as if you had booked two weeks in advance. (I'm assuming you go in to an AA office to pick up the award; admittedly the $50 fee includes express delivery).

UA doesn't charge a last minute fee so no need to have a certificate in hand (and risk the re-deposit fee a year later).

In fact, last night I booked a UA award for a friend in Seattle to fly to Houston tomorrow and visit his Mom. I went to a San Francisco ticket office today and signed for the miles; he can pick up the [e-]ticket tomorrow at SEA-TAC airport...and no fee even for that!