Iain is joining LBC 97.3 fm in the new year: He is also sitting in for Clive Bull all next week in the 10pm - 1am slot.
Veteran presenter Hayes is also departing from LBC, with his Friday to Sunday late show handed to Iain Lee, of RI:SE and The 11 O'Clock Show fame.
The Chrysalis chief executive, Phil Riley, said it was time to "refresh and refine" the station a year after the last rejig and two years following its relaunch.
"It's about where we want the station to be in five years' time. We are going to invest in Iain Lee for the long-term. We think he's a big talent."
mediaguardian