@Angharad01
Sorry to hear about your ds's diagnosis. How resilient he must be going through A levels studies, med applications and dealing with this. He sounds like a tough cookie!
Having said that I'd suggest he asks the uni about deferring. Medical reasons are considered differently than just your average dc who fancies going backpacking to exotic beaches. It's in the uni's and your ds's best interest that he feels at his strongest when he starts the course.
The first few weeks of uni (whatever course you're doing) are times of high emotion, high stress, great excitement and often some exhaustion and burnout a few weeks in. (Mine were both adamant we wouldn't see them until Christmas but came home about 5 weeks in, full of stories, white-faced, with bags of dirty washing and slept for a weekend!
) Whether your dc prefers libraries or night clubs there will be times they get little sleep and eat irregularly. Trying to cope with this while also getting used to meds and triggers etc sounds beyond tough.
I'm sure the uni will be fair. A friend of ds was diagnosed with a serious chronic condition (not epilepsy) at about this stage in his A level year. The uni agreed to hold his place open until the following year or even the year after if he needed the time.
Not starting this September would also buy him a little bit of time to relax, recharge and think about reapplying to the closer uni with his grades in hand if he feels it would be more sensible to be close to home longer term.
Good luck to him.