I agree with your comments about supply chain issues like glass vials, could turn out to be the weakest link in the supply chain, not so much for the Pfizer product as product is finished in house and production planning would account for, but maybe for third party fill and finish of the Oxford jab.
I'm not so sure about community pharmacists being engaged en masse at this point in time. Boots are setting up a few hubs at large pharmacies to vaccinate 1000 a week, but your average community pharmacy couldn't do anything like that, and when you consider a 6 hour shell life once a dose has been extracted from a vial, and the fact that the SKU is 10 vials, community pharmacists could remove one heck of a lot of stock from an already friable supply chain, and potentially waste stock too.
Additionally, unlike the flu jab where appointments can be made for anyone, or even walk in service, the Covid jab will need to be given in priority order, and how is it all monitored? Pharmacy IT systems do not link to NHS patient data. Finally, according to the PIL patients have to be given a date for their 2nd jab at the time of the first, yet another administrative issue as the pharmacist will need to be sure he has stock available for these.
All in all I think pharmacy involvement would be best at a time when vaccination is open to the general population.