I bought Envoy upgrades PHL-LGW 3 weeks ago. I needed two and I wanted to make sure they were side by side, so I called at 29 hours and 55 minutes. At that point the seat map was showing 6 open seats, with two pairs and two singles.

When we flew, there were 3 open seats, so I guess only one more was taken after I booked our upgrades. Coach looked pretty full.

I had coach award seats and I feel the upgrades were worth the money. We actually got several hours of real sleep and felt much better upon arrival than I have felt after going TA in coach. I'm not sure I would pay a couple thousand for Envoy seats, but for the upgrade fee, it's a reasonable value.

We returned LGW-CLT on the 17th in coach. That was only about 60% full and we were able to shift around and get seats with nobody beside us and nobody reclining into us.