Turns out it’s the manual release catch for the electric charging point in case of the charging cable not being able to release itself automatically.
Cheers all.
Thanks Er1c,
It disappears into the padding of the arch (heading towards the front of vehicle.)
Thought it might have been to do with the handbrake (it’s a hybrid also) but it doesn’t reset itself once started.
Vehicle doesn’t have a spare.
Cheers.