Originally Posted by
StayingHomeIsBetter
While I haven't purchased an UP fare in a long time, were I to do so I would keep a screen shot of the Y fare that I could have otherwise purchased, on the day of purchase... just to substantiate any potential refund claim.
Didn't the OP say the I "up" fare they purchased was the cheapest option available? I think this would be a different story if an -up fare was booked when cheaper options were available (i.e. took the 'first available for xxx more' offer). But if the OP were only looking for the cheapest Y seat and got lucky to find that it was an -up fare, in the end they got what they originally expected.
Delta giveth, and Delta taketh away...