So I repostioned my reverb remote by a 1cm and changed the angle slightly and now the post behaves like it’s in treacle. If I move the speed all the way up it won’t budge at all. Is that air in the system?

Lowered the post?
Stealth?

I slammed mine for the Alps and got the same issue, turned out I’d put a link in the cable in the bottom of the seat tube.

Try raising it again and feeding the cable through the grommet in the frame as you lower it

I’ve managed in the past to move the lever slightly and have this problem. The cause was that the back of the button was bottoming out on the brake lever clamp before it got to full travel.

Yes stealth. Will have a look at that. Could of made a silly mistake like you Robin cheers.