The van starts first time... A bit of a surprise (she had been standing for a few weeks)
Cadover Bridge has parking spaces ... Can be full on a sunny day......surprise
Nice walk, nice picnic, pack to move on and shut the sliding door - it comes away at the rear SURPRISE

Had to call the mendyman (hadn't taken any tools) and with the aid of the Haynes manual borrowed from the driver of the T25 next door (another surprise) we got it remounted.
Still not sure how/why it got detached in the first place - any thoughts?