Hi Mohan,
As per my understanding, there will not be any class transferred and assigned at the PDS level. Only the object dependencies from Super BOM and Super Routing in ECC will get assigned in the PDS, if you are using Variant configuration.
Then the CDP class will be assigned to the resource in which you want to define the blocks.
Could you please elaborate the issue little more with screen shots?
Regards,
Manimaran M.