Vaccine appointment cancelled: common?

[bathsh3ba]

I booked last week via the central online booking as Group 6 and my first slot was the week after next. I got a text tonight saying my appointments had been cancelled (no reason given) and to rebook. I logged straight on and managed to book exactly the same first slot and a slightly later second slot (a week later than before).

I'm now wondering why it might have been cancelled and if this is a common occurrence that I should expect to recur again in the next 10 or so days till my first appointment? It's left me a bit nervous...

Some people near me had their second slots cancelled because they were only 8 weeks or so later, rebooked for 11/ 12 weeks later.

Probably just due to supply issue.

Almost certainly supplies not delivered

To those saying supplies not delivered, I would understand if it was cancelled the day of, or day before, but this is 10-12 days in advance. Would they know about supplies that early? I wish I could get an earlier date so there was less time to worry about it being cancelled again!