Change business partner for purchasing organization.

Hi Friends,

The scenario;

Originally the purchasing organization PURORG1 assigned to business partner BP1 (transaction PPOSA_BBP).

There are many internal address address created for this PURORG1 (which attach to BP1).

After sometime we found all the internal address is missing from the purchasing orgnanization PURORG1. Then we found out that now the PURORG1 is attached to business partner BP2. From the table level I could see the old address is attached to BP1.

My queries are.

1) Can we find out who change the assignment of the BP and purchasing org?

2) How can we remap again the old business partner BP1 to PURORG1?

3) or is the any way to remap all the old address from BP1 to the new business partner BP2?

Please help me to sort this out.

many thanks

Mike