Today the UK Prime Minister returns to work. His first task is not to decide when to end the lockdown. Instead, it must be to manage public expectations about the length of lockdown. He needs to speak to the British people today.

Evidence from Wuhan showed that a 10-week lockdown worked to cut community transmission. That suggests the UK lockdown should last until June 1. This would give us time to ramp up testing, recruit the workforce to contact trace, and to produce real-time Ro (Rt) to guide lifting.

Also, look at Italy. Their lockdown began March 8-10. They are making minor adjustments on May 4 (8 weeks; take-outs from bars/restaurants). Museums/libraries open after 10 weeks. Dining in restaurants June 1 (12 weeks). Italy is following the Wuhan timeline.

So what you could say is this: we must use May to build the capacity to end lockdown on June 1. We must use May to see new infections and deaths continue to fall. We must use May to plan a recovery plan for the nation. We must use May to think about what kind of future we want.