Just to check in, I'm fine - thanks to all who sent me messages. I was (deliberately) running late this morning, since I needed to sign up with a local doctor, so I only made it about halfway into work before I had to turn around and come back. As I came back through central Croydon, the council were telling all the shops to close. I've sent a message to the local SJA people, telling them that I'm available if they need me, so I may disappear off later.
One general note - now that I work in a hospital, I have to keep my mobile turned off while I'm in the building (i.e. 9-5). So, if I had arrived on time this morning, you wouldn't have been able to get hold of me, so please don't panic and think the worst in a case like that.
Anyway, it looks like most of the people I know have reported that they're safe, which is good to know.