I booked DEN-PSC for today a while back and the seatmap was fairly tight. At that time there was one exit row seat open (I grabbed it) and two other seats (row 6 and row 3). I’ve been checking upgrades and seat assignments on all my flights for today and no other exit or bulkhead seats had opened up on this leg. When I did OLCI this morning, the entire bulkhead row appeared as available . So either a party of 4 with status bailed out at the last minute, or UA blocked all the bulkhead seats well in advance. Anybody else experience this?