Originally Posted by
earck
PM here. I've had this happen twice now. The first time, the C+ upgrade eventually cleared a couple weeks after booking. But, I also have a Vegas flight for CES which has not cleared for me.
My guess is that they expect to be able to sell them all due to high demand.
Update: My C+ upgrade cleared this morning. 2 months after booking...
Interestingly it cleared me, but didn't assign a set. Good thing I checked, because there was only 1 non-middle seat left.