When we arrived, there was a red Golf already parked in the lay-by. We waited a few minutes, hoping it would leave: instead, an AA van pulled in behind it: the Golf had broken down! Still, both the owner of the Golf and the AA mechanic were engrossed in fixing the car, so we don't think they spotted us retrieving the cache, making our swaps, and placing it back in its hiding place.
Took two foreign coins; left a mini notebook.
Thanks for this unusual cache!