Can't tell if I'm the unluckiest EXP, or DEN has become a hotbed of EXPs or cheap buy-up offers. A flight I was certain to get an upgrade on, DEN-CLT red-eye on a weekday night, showing J4 with less than 4 days out is now zeroed out in the front and seat map is fully booked. Sometimes I wonder if I'm getting skipped over or people are buying up to F.