Coronavirus 19 May 2020 Evening summary: Top government scientific adviser casts doubt on 1 June school reopening Sign UpGet the New Statesman\'s Morning Call email. Sign-up Professor Angela McLean, the government’s deputy chief scientific adviser, has said planned changes to lockdown are based on having a “highly effective trace and isolate system… in place”, casting doubt on whether she and other experts will back the opening of schools on 1 June. The government initially said it would have a contact tracing system, which will comprise an “army” of more than 20,000 contact tracers alongside an NHS app, ready by mid-May. Yesterday, it simply said it would be ready “in the coming weeks”. When it was put to McLean that a trace and isolate system would therefore not be in place by 1 June, the date the government wants some primary schools to open, she said that she expected an update on the readiness of the system on Thursday, but did not elaborate. Earlier, she said scientific advice on easing lockdown measures was "based on observed measured of incidence, not on a fixed date". Her comments put further pressure on the government to get its contact tracing app ready before June. If it becomes clear the system will not be ready, it could mean that scientific advisers are added to the list of those opposing a 1 June school reopening, which already includes teaching unions and local authorities. At this afternoon’s Downing Street briefing, McLean also said the UK was "aiming to emulate" South Korea in its "inspiring use of all different types of contact tracing". The country is currently using GPS phone tracking, surveillance camera footage and credit card transactions to trace infections. Lastly, Environment Secretary George Eustice announced a new "Pick for Britain" website where people can seek jobs picking the summer harvest. An hour after he spoke, the website was still displaying the message: "The service is unavailable". › Reopening schools is a question of logistics, not of risks Subscribe For more great writing from our award-winning journalists subscribe for just £1 per month!