Saw that happen once, trying to take the wife on a working trip. First Class wide-open until two hours before departure...then, 12 non-revs showed up that were more senior than Moses.

I’ve seen this happen about three times. To me it seems there may be a crowd of senior folk who look for open flights just to jump on...hitch-hiker’s guide to the universe via pass-travel.

Westbound, it can be a weight limitation...I’ve seen that a few times, despite lots of open seats.

It is possible that another carrier could have cancelled, and those pax are being put on our metal. Saw that the first days after the Max was grounded, with SWA pax.

eRes is pretty good overall, but there is always a random element when NRSA. And some markets are worse than others (Italy difficult; Germany usually not too bad).