As I sat outside in the sun drinking my coffee this morning I decided I would ditch today's to-do list and just spend the day reading and absorbing Vitamin D.

Then my phone rang. Could I do a shift at the vaccination centre starting in 70 minutes' time?

Since early February, when I finished my St John Ambulance training, there has been such competition among volunteers for shifts - with some shifts over-subscribed tenfold - and the app for signing up for shifts has been so difficult to use, that I got in touch with the local organisers two weeks ago to say that I wasn't interested in competing and that I was going to stop looking for shifts but that if I was actually needed any time I was still willing to volunteer.

So I said yes.

I brought in the washing, changed into my pristine St John Ambulance t-shirt and looked for the ironing board so I could iron my mercifully newly-washed black trousers. In the possession share-out I got the dubious spare iron (perfectly justified, since my relationship with ironing is worse than dubious) and I haven't had reason since I moved in last May to check whether it works. Anyway, I found it, and it does, so when I leapt onto my bike I was looking as respectable as I am capable of.

In Oxford's Mass Vaccination Centre all the vaccinations are given by NHS professionals so the volunteer role is to welcome new arrivals, keep things running smoothly, spot anyone, either before or after the vaccination, who may be agitated and call for professional help if it's needed. All five of us this afternoon were doing our first shifts - admirably briefed by experienced volunteers from the morning shift.

The session was moderately busy late lunchtime then quiet then much busier from 5pm after normal working hours. It was interesting watching the queue build towards the end of the session when, so as to minimise waste, each vaccination 'pod' closed down when it had finished a vial of vaccine. At the end only one pod was open and after the last member of the public had been vaccinated there were two doses left. They were initially offered to two young volunteers but as they were both under 30 and the Astra Zeneca vaccine is no longer recommended for under-30s I was suddenly in the running for my second dose. But two other people who were higher priority than me were found in the building so I cycled home unrevaccinated. 

It's a really impressive operation. And my feet know they have been stood on for six-and-a-half hours.