Re: whether it would be a "punishment" to be assigned to the mop-up group to be got round to when everyone else is sorted, if you refused AZ without clinically-identified reason — not as such, IMO, but I think it could legitimately be argued that demanding a particular vaccine without an objectively-identified medical need may have to be disincentivised in some way, as large numbers of people doing so would disrupt the mass vaccination programme, which could have serious consequences for the country as a whole.
Suppose the AZ vaccine, while preferable to remaining unvaccinated for the vast majority of people, really is riskier and less effective than the others. In that case, on an individual level, it makes perfect sense to refuse the AZ if the result is likely to be "Okay, we'll give you one of the better vaccines, then". And if that was the likely response, lots and lots of people would, quite rationally, request the better vaccine for themselves.
Unfortunately, there's not so much available of the other vaccines, and they need to be earmarked for certain people — second-dosers, those who've been clinically evaluated as being medically unable to have the AZ, and so on. Plus, letting people pick and choose based on their own personal preferences is an admin nightmare and slows everything down.
In a situation where most of the available vaccines are of a slightly inferior type (while still being well worth having), the only way to allocate these vaccines fairly and administer a mass programme efficiently is to have objective criteria by which to select the people who will get the better ones, and for those who don't fit those criteria to be told, "It's this or nothing for now — and the evidence we have shows that of those two options, taking the AZ is likely the safer choice, but you're welcome to go away and wait for the mop-up, and hope you'll be offered a different vaccine then".
If you want to think of that as a punishment for not being willing to accept (what you believe to be) an inferior, higher-risk vaccine, then fair enough, but there's no perfect way to do this thing.