It's interesting, though, as he is unwilling to believe that his pneumonia in January may have been the cause as it predates the first known UK cases. He may be right but more instances could come to light as this kind of testing kicks off.
France has found a case from December via re-testing hospital specimens.
https://www.bbc.co.uk/news/world-europe-52526554
Absolutely. We also know that (I think this is correct as of writing) that the first death reported in the UK had 4-5 that preceded it in other geographical areas and settings, with quite a number just after it as well, whereas I think what he's written about the first confirmed case is still true (as there wasn't much testing and other factors). Other studies point to the virus circulating in larger numbers than thought in January in the UK. It wouldn't surprise me if it was discovered that the virus started circulating in the UK at the end of December and certainly earlier in January than was confirmed.
I think some of it's probably journalistic integrity and ethics. If I were writing the article although it's personal, there is a sizeable minority of UK society that think they had the coronavirus in December/January. Some of those people will be correct. Many will be wrong. I would not particularly be wanting to write something, nor would my editor want it played up the yeah I had flu in January and people read that and then it changes behaviour. Some people say yeah I had the coronavirus in January and behaviours change substantially such as seeing neighbours, friends and family in large groups all the time or giving up hand washing and distancing. I've had this with my dad the last few months where he's had a number of infections and been PCR tested 4x and serology tested 2x. Whatever he had as of the time (or shortly before) wasn't the virus. There will be people over the next 2 months (many will be care and home workers) who test antibody positive so I expect the article is written for them.
I have a friend that think he had it in December. I am slightly curious as like the BBC reporter if I've had it then I either had it in February or been asymptomatic. Similarly I know my father hasn't had it (phew).