I know my reverb should have 250psi in it, but is this the pressure when the post is in it’s extended or compressed state?

No answer to your question but another question – how long can you leave Reverbs compressed? I often leave mine down for 2-3 hours when it’s wedged in the car but a mate was telling me this can lead to problems. Anybody know?

I see no reason they cant be left compressed. Mine is often left for days.

In answer to both questions – i top my pressure up extended and regularly leave my reverb compressed for a few days at a time.

Nothing bad has happened 😉

Only issue I have heard of leaving them compressed is if the are in direct sunlight. Often leave mine overnight as it has to be down when on the bike rack when we are camping.

Mine was down for months, never had an issue.