Outdated info iirc. This was the case with android 13 for fp3, which they skipped completely and jumped to 14. They also still push updates regularly for all phones later than fp2.

And if you want bleeding edge updates, no phone maker does that and youll have to look at lineageOS, which tends to break things once in a while.

( im a fp4 user with lineageos running android 15, sep 3 update )