Alex Mahon must hit the ground running at Channel 4

Problems facing new chief executive include stopping its young audience from switching to Netflix, and pressure from government for a move out of LondonIf timing is everything, then Alex Mahon’s arrival in her new job as chief executive of Channel 4 on the eve of the final of The Great British Bake Off could not have been planned better. The new-look show’s critical and commercial success has more than justified the £75m spent taking it from the BBC.Mahon, who turns 44 this wee