Project Conversion

Hello,

I am dealing with a Project Conversion FD.My client is already having SAP-PS implemnted. However they are implementing IM now. My question is after go live of IM there will be some open projects in the system.

The approach i am thinking is to the extract of the projects in a flat file and map the project against Interest Profile, Overheads etc and reload the projects.

My question is now some of the project will be partially confirmed. What will be the impact on the total cost because of loading Interest Profile, Overhead key etc. Will Interest and Overhead be recalculated for such confirmed activities or will it be applicable for only unconfirmed activities.

Is there any other better approach?

Thanks

Sarang