As we all know, the horror story is having 21HJ on an XP2 and getting swapped to an XP1 (on the 2, 17-20HJ are crew rest seats which means 21HJ has more leg room than the bulkheads even. I'm doing SFO-LHR tonight, and when I booked, it was an XP2. 17AB (playing it safe) were taken, and so was 21HJ, so I took 17G. (Right side aisle in center 5) Go online this morning and it's now an XP1 with 17J available, which I immediately grabbed. Could it be a swap b/c it was Y1 at that point? I called CS to make sure my 17J took (yes) and she said it was oversold. So does UA do the XP2 to XP1 swap to free up 6 seats?