Ross, who moved across to run C4's in-house film-making unit in 2002, is expected to take back control of drama with a joint brief across film and television.
C4 has yet to determine Ross's precise brief and the reporting structure for the new role. However, she is expected to continue Yorke's strategy of putting returnable series in the Tuesday 10pm slot.
As the channel's head of drama between 2000 and 2002, she was responsible for commissioning the first series of Shameless and Teachers , both of which have been recommissioned.
Of C4's current slate of dramas, NY-LON , the transatlantic love affair that failed to excite audiences, is not being recommissioned, while No Angels ' second series will broadcast next year. Yorke's other major commission, The Ghost Squad , is set to go into production shortly for delivery in August next year.
Ross currently oversees single TV dramas and films for theatrical release and reports directly to chief executive Andy Duncan. Ross was formerly head of drama for the BBC's now defunct Independent Commissioning Group.
Yorke, meanwhile, is returning to the BBC, taking his C4 deputy, Lucy Richer, with him, to take up a new role of controller of continuing drama series and head of independent drama.
Together with Richer, who has been appointed as joint head of independent drama, Yorke has been charged with increasing the level of indie drama produced in the regions.
BBC controller of drama commissioning Jane Tranter said: '[John and Lucy] will be the first port of call for all London-based independent drama.' She added the pair would also have a specific brief to develop and produce drama based in the north of England.
'Plans for the further expansion of drama production in the nations and regions, which will also play a critical role, are currently being developed,' she said.
The BBC also announced that head of drama serials Laura Mackie has been given a specific brief to develop drama in Birmingham and Manchester. She will oversee the in-house drama department, which brings together returning drama series with the serials division.
Yorke, a former EastEnders executive producer, and Richer have been brought in to fill the gaps left by drama executives Mal Young and Gareth Neame, who are quitting the corporation in the new year to join the indie sector.
Current BBC controller of continuing series Young is leaving to head the drama division at 19TV, while head of drama commissioning Gareth Neame is to join indie Carnival.