For an anal old guy like me, knowing that the problem was present would drive me nuts. I build my bikes to the absolute best of my ability, resources and components availability does impact that, though. With that in mind, I could not leave a stuck post, or stem or pedal, untended.

But that is just me.

You might just ride it for a while, with the seat clamp bolt loosened off. Dribble penetrating oil, or something like that into any open crevices, and then ride the bike. With a bit of luck, and help from you butt, the post just might loosen up. Give it a try. This has worked for me in the past.