On Monday night, I arrived in the short-stay car park at Oxford rail station at 8.12pm. I duly got a ticket from the parking machine, which gives drivers 20 minutes’ grace before slapping on a £3.50 charge. The ticket announced a time warp difference of six minutes, effectively giving me 14 minutes before I had to pay, which seemed a very convenient mistake of the machine for APCOA. Is this a sneaky way of catching drivers out?

R Lewis (Ms) Edinburgh Drive, Kidlington