Thanks Senior Pilot.
I have tried clearing my cache/logging out/clearing browsing history etc, as suggested several times.
Also posted a test post to the F1 thread, but although my post is indicated as the most recent addition, I can still only see up to Oct 17th, post 880 when I log back in to the site.
I'll try again later from my desktop PC, I'm currently doing all this from my mobile. Fingers crossed.