I book a lot of Y fares through my office because, lucky for me, that's the contract fare from DC -> SLC. I have always gotten upgraded, which isn't really a surprise. But this doesn't mean my travel experience is nerves-free, and here's why - my company doesn't "purchase" the reservation until 2 business days prior to travel. I usually travel on Sunday, so this generally means my tickets is purchased on the Thursday prior to travel. Until that day, all I really have is a reservation for a Y-fare ticket and an upgrade "request." Now, the Thursday before a Sunday trip is, I believe, inside the DM upgrade window. What that means to me, all things being equal, is that a DM who has purchased their ticket will get the FC UG on Wednesday, reducing the number of FC seats available by the time my ticket is purchased on Thursday. UNLESS, by having a Y-fare reservation, DL holds an FC UG for me, assuming I'll buy the ticket, and if I don't they'll release the seat at the gate. Is this the way it works? I honestly have no idea how DL treats Y-fare reservations vs. actual purchased tickets. Since a Y-fare virtually guarantees a UG if available, do they hold an FC seat, or let the cycle run and if a seat is available when your ticket is purchased, lucky you, if not, not-so-lucky-you?