Ok, I've got a sort of fix but it's a bodge.

 

Before I put everything back together I put some sticky back soft pads on the flap to stop it from closing properly as I found the motor doesn't fidget and make that annoying motor sound. If you hold the flap and fight against the motor I found it cuts out and stops as it thinks it's obstructed so this helps.

 

Problem now is I have an airbag fault light on the dash that needs clearing... hoping disconnecting the battery and reconnecting will reset it. If not my MOT is due soon so will take to the local garage and ask for it to be reset + if they could reset the climate control software to see if it cures the problem.

Airbag light needs to be cancelled using VCDS software. See the VCDS forum for a map of members near you who can help for beer tokens.