need your help - plzzzzzzz guide me

can anyone pls guide me that can i prepare for CS exeutive exam in just 15 days..as i have my IPCC exam in may that will be over on 17th may and CS exam will be start on 2nd june and ill be having only 15 days to prepare for CS.

should i fill up the exam for both groups or only for one group or should concentrate only on IPCC?? need ur guidance from those who cleared CA & CS both together?????