Nickolash, that is a rather sarcastic reply. I was answering a PP who didn't think the change was due to an algorythm. I don't know how these things work so have joined this site seeking information. Fact is, on an upgrade flagged as a deal at $808, when I cclicked review and pay, some red type appeared saying the fare was no longer available and the the price jumped to $1,500. A near 100% increase seems rather odd. Especially when I then paid the new price and the same seat was available and there were no seat changes elsewhere. So makes one very wary when taking up anything flagged as a deal as you now never really know what the price is going to be.