I’m sorry that’s happened too.
I wonder if an email to the Head of Dept outlining the situation of an offer last year, then the health crisis and delayed A Levrls and reapplication might help.
I assume he has same predicted grades as last time? If not, the situation might be clearer and less worth querying.
It’s quite possible only an administrator saw the application and knows nothing of last year. The Head of Dept might be able to look at it in a more nuanced way.
I wonder if the email (sent from son not you) could ask if they might re-consider or if they would advise going for an appeal.
Best case scenario is Head of Dept simply says an offer can be made in the circumstances. Hopefully even if that doesn’t happen, reasons can be given for the rejection and useful advice about if to take it further.
You want the email to get to the right person so be careful in finding out who that is and in tracking down their email. I’d do it sooner rather than later as places still available to offer will be reducing.
All the best - there could be a good outcome here. But I’m glad he has the E offer as that is brilliant and some might think preferable.