How long do you give it before Labour abandon their promise of golden hellos for new teachers? Shadow education secretary Bridget Phillipson has insisted their proposed £2,400 welcome bonus wheeze will be fully costed, funded by a tax raid on fee-paying schools.

It is not yet clear whether Labour has considered that putting private education beyond the reach of tens of thousands will mean many pupils pouring into the state system, at a cost of hundreds of millions every year.