Originally Posted by
dgtsf
Thanks for the tip.
FCM?
Sorry, I'm new here and there's a s**t-ton of acronyms I'm still wrapping my head around. A glossary as a sticky post would be useful around here

FCM = First Class Monetization.
They are upgrades offered at any point before departure (but usually at check-in). They tend to be a big discount off of the cost of paid first. They are most likely to pop up on leisure routes, and the prices are often pretty good.
It is impossible to predict when or if you'll get an offer, and whether it will be a good deal or not.