I booked cheapest flights I could find for myself and my partner during the promotion period. It took a bit of back and forth and emailing passport scans, but we each got the 90k Avios. I redeemed my and my partner's Avios back in September for LAX-MAD (J), MAD-BCN (J), BCN-MAD (Y), MAD-LAX (J). Had to transfer some BA Avios from both of our BA accounts to our IB accounts to have enough. We both have a few thousand left over. So far it all looks good.
Our stupid cheap flights have all had schedule changes, but I'm assuming that if I were to call and cancel because of that, the 90k Avios each would be clawed back.