I've got to go to an out of hours clinic this weekend. It is at a doctors surgery that is usually closed at the weekend but open for an hour for patients to visit the wound clinic.
Last weekend someone drove me and the car park was full of people who had gone shopping in town - they weren't supposed to park there.
This weekend I'll be driving myself...so if the car park is full of shoppers again, AIBU to block one of their cars in and leave a note on my windscreen to say 'visiting wound clinic at this surgery between 2-3pm'.