And not for the first time 
Yrs 10 &12 were originally to "start returning" from 1 June and we planned for that then during half term we were told not until 15 June and had to unravel the plans, so presumably there was something in the science to suggest schools needed to take things more slowly.
At the same time, some shops will open earlier than expected and some social restrictions have been eased.
Why do both those things make sense?