Your regular reminder that deputy chief scientific adviser Angela McLean said earlier this month that any changes to the rules should be based on "observed levels of infection... and not on a fixed date".

Yet the PM has a string of dates, June 1 (primaries, BBQs) June 8 (quarantine for arrivals), June 15 (non essential shops, secondaries), July 4 (possibly pubs, restaurants).

He keeps saying the dates are all "conditional". But the one key condition *missing* is a fully operational (at local and national level) test and trace scheme.

Imagine if he had followed McLean's advice. He could have given rough timetables "next few weeks/months" while ensuring the number of cases/test+trace drove any policy.

And instead of pre announcing changes to lockdown (surely I'll advised to say on Thursday 'hey you can BBQ on Monday'?) better to say, 'I can announce that x condition has been met and from midnight tonight y change will happen'. Works for Budgets on booze/fags tax.

*ill advised* (apols typo)