Dominic Cummings and Seumas Milne: In the firing line or just being used for target practice?

On a day when Prime Minister Boris Johnson appears to have clinched a deal with the EU - although not yet the blessing of his DUP allies or the UK Parliament - swirling media reports predict the end of the tenure of his controversial special adviser, Dominic Cummings, as well as that of Jeremy Corbyn's comms chief, Seumas Milne. But is it just all just hot air and spin?