Originally Posted by
JoeWoodstock
On the mobile app, I see a button there to Upgrade Seat, and I can then see all the cabins, including First. If I click on one of the empty, available seats in First, nothing happens; that seat doesn't get selected. So, I guess that Upgrade Seat "feature" in the mobile app isn't what you're talking about with FCM?
FCM has become sort of an umbrella term* covering a variety of situations
1. when the difference between buying Y and F is surprisingly or anomalously low
2. an offer, when viewing an itinerary, to buy up to F for a surprisingly or anomalously low amount (usually, it amounts to the price difference between Y and F in case #1)
3. an offer, at check-in, to upgrade to F for a low amount
usual caveat that #2 gets the benefits of an F ticket like increased MQMs, and #3 is handled more like a comp upgrade and does not. My recent comment was merely an observation, for people wondering why they never see #2, or never see it on some routes but do see it on others, is that it's functionally random from a customer perspective, and you can always obtain it manually by calling in to pay the difference if the price is right for you.
An offer to upgrade your seat by choosing a different one on the seat map would fall under #2 or #3 depending when you're doing it, and whether from the desktop web site or the mobile app. If it's not working to an app bug, that's a separate topic.
*perhaps to the chagrin of people who like their terminology more precise, which occasionally describes me, but for some reason this doesn't bother me