@ robomatic: we have been told not to phone our GP’s surgeries to ask about getting vaccinated as it’s “don’t cal us, we’ll call you or send a letter”.
However there is a phone number on my husband’s letter to call if you have any problem with the appointment given, so I might just call that before the day to see if there is any possibility of just turning up and getting done as you suggest. May be different over here though :-(