Boris Johnson’s predecessor was destroyed by her inability to meet deadlines. Theresa May extended the Brexit transition period so many times that her party eventually turned against her. Johnson, who was notorious for pushing deadlines when he was a journalist, is now discovering the political problem with missing dates. The Prime Minister may still be flying high in the polls but if he cannot meet the new date for ending restrictions — 19 July — then his own MPs will lose faith in his ability to restore normality.