Going to repeat my personal rule for judging all "new strain" or "new variant" stories... Viruses mutate all the time so it's important to ask whether the behaviour of the virus has changed. We've been given the "scare" but not the "answer". What @MattHancock said is: "Over the last few days...we have identified a new variant of coronavirus, which may be associated with the faster spread in the South East of England."

Here's the modelling for winter that is leading to a new lockdown discussion. Black line was the government's "reasonable worst case scenario" capping out at under 1,000 deaths per day. (from the brilliant @bbclaurak) Sage (scientific advisory group for emergencies) uses disease modelling from multiple groups, which each use slightly different methods. Two (LSHTM and Warwick) predict peak deaths around 2,000 a day and Imperial above 2,500.