Another data point - one-way LAX-BOS in first week March weekday, on what is currently slotted as a321Neo, only took 1 MTM certificate for the leg. I will say, if/when they start letting us see how many certificates it'll take before booking... if the ones I locked in at 2 MTM per segment are then showing as 1 MTM, it's an obvious cancel-rebook-reupgrade. How will JetBlue IT handle canceling a flight where you've already applied certificates? Any bets on the smoothness of the process in getting access to those certificates again?