I'm having trouble parsing this sentence. If it has 2 F seats left then what is it that's sold out? The second half of your sentence is unclear too. Screenshots might help make sense of what you think you're looking at, and if you gave flight numbers people could look up the actual inventory for sale on EF. (Less reliable for Y if they're willing to overbook but they generally don't overbook F so whatever's left there should be exact.)

In the time since your first post to a more recent one based on what you reported the # of F seats actually seems to have gone up from 3 to 4, so some people who were in F may have canceled (common during COVID given change fee waivers etc.) so you can't necessarily draw conclusions about numbers based on what things looked like before/after you got upgraded.