Some parts of the timeline that I reckon will be important.

27 March: Cummings seen running from Number 10.

30 March: PM spokesman says DC is “not in No10 today and he is self isolating after developing symptoms over the weekend."

31 March: Spokesman: DC is "in touch with number 10, but he is at home. He is self-isolating because he has some symptoms."

Writing in the Spectator after he returned to work on April 14, Cummings said both he and his wife were in quarantine together, with their child.

And Mary Wakefield wrote that 24 hours after he had “rushed home” to look after her (Friday 27 March), DC had “collapsed” and couldn’t get out of bed for 10 days.

All of which is in the service of saying that when Number 10 puts out a statement that is directly contradicted by Dominic Cummings, his wife, and the Prime Minister’s official spokesman, you’re entitled to treat it with some scepticism.

Oh there’s someone else who directly contradicts Number 10’s statement. Who was it now, I had it here just a second ago <ruffles through papers>...The Police. Durham Police.

https://www.mirror.co.uk/news/politics/dominic-cummings-investigated-police-after-22072579