OK then, I'll have a go at the pile on.
Its just admin. Organising 14 million injections in less than 6 weeks. In the middle of winter when letters are often taking longer that usual to arrive. What would you have said if the letter had been late?
The over seventies had to queue in the snow this week where I live and most of them put up with it because they know what a huge undertaking this whole, logistical event is. A woman in Dundee walked through the snow for 90 minutes to get her jab because she didn't want to miss it. But your letter was early. You could have said that it cost you some time, but that you understand how complicated it all is. But no. It's a cock up.
Sorry, no sympathy.