My guess is they didn't realize exactly how much the visa rules had changed. Since the initial entry officer didn't ask enough questions they were let in, and they probably found a lawyer or called the helpline and they said of course you can apply in-country. My dad can't go on long drives without blood clots forming in his legs (for no known reason they've found yet), he certainly can't take a flight, but I have a feeling UKVI would still call him healthy. They are trying and paying the fees, as long as they meet all other requirements (just not applying from outside the country), I think given their ages the home office should use some discretion. They might not even use the internet very well and we know how difficult the visa info can be to navigate, and how bad lawyers can be. Articles like this pick and choose what to share so I'm sure we aren't getting the full story!
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