According to sources within the agency, Palmer decided to leave because he felt unable to settle into the culture at the agency. He leaves without a job to go to.
One source said: "I don't think he felt comfortable and neither side felt like it was working as well as it might have. He wasn't here long but it felt better to resolve it quickly in a mature fashion."
In light of his exit, WCRS has restructured its planning department, and does not plan to recruit for a replacement executive planning director for the time being.
Clare Hutchinson, a senior planner who joined the agency from Abbott Mead Vickers BBDO in January, will now become the head of planning.
Giselle Okin, a senior planner who works on Weetabix and Transport for London, will become her deputy.
Will Orr, the managing director at WCRS, said: "Clare and Giselle have a very clear vision for planning at WCRS. Under their leadership, it will go from strength to strength."
At AMV, Hutchinson ran Clarks and Diageo. Before WCRS, Okin worked at Bartle Bogle Hegarty, United and TBWA/Chiat/Day.