Clearly not saying anything about out of hours parking.
I'm not sure that's quite true. The signage states that a stay of up to 30 minutes doesn't require any validation (essentially meaning 30 mins free parking).
It also states that drivers may stay for up to 2 hours
if they spend £5 in store. It follows that you can't spend £5 in store when the store is closed, and therefore you cannot stay for up to 2 hours when the store is closed.
