We have a BOM with many levels, for this example lets say 9 ;levels down. At Level 5 is a component which we purchase from a Vendor.
The purchased component actually has lower levels in out BOM because some of the materials that the vendor uses are initially purchased by us and sold to this vendor.
MRP runs today, but stops planning when it hist the Purchased item due to the PM Code being a "P".
We need the system to plan the lower levels, but are concerned that if we change the PM code to an "M" it will cause more issues with Cost Roll ups and other reporting.
You could treat the 5th level item as manufactured with sub-contract conent, the lower levels being the material you issue to your supplier to the processing you require.