As the Government sold off its last remaining stake in Royal Mail in 2015, then chancellor George Osborne hailed a “milestone moment” that would secure the postal service’s long-term future. Yet less than a decade later, that future is already in doubt. In its damning report, regulator Ofcom warned of an “increasing risk it will become financially and operationally unsustainable in the long term” unless Royal Mail is allowed to ditch its requirement to deliver letters six days a week.