Byron has taken up a new role as Royal Mail’s network and strategy director.
He’ll be joined at the postal service by Heathrow chief operating officer Emma Gilthorpe, who was named Royal Mail’s new chief executive on Tuesday (2 April).
Gilthorpe will take up her new role in May.
"I’m delighted to share I’m starting my next adventure today as network and strategy director at Royal Mail," wrote Byron on LinkedIn. "An iconic UK brand with a 500-year history – I can’t wait to get going."