Here are a few more things to consiider.
1. As mentioned by another respondee, the item B/P record overrides the The B/P constants value if there is a difference. The B/P constants value merely provides a default value for when the Item B/P record is created. Try changing the B/P record and see if the result is different.
2. On the B/P record, is the Lot Process type set to require lot numbers, or is it set to Blank, or zero?
3. On Mfg Constants, is commitment control set to Primary location or is it set to "split - don't cross B/P boundaries"?
4. What happens if you create the lot records BEFORE you attach the parts list?
Sometimes we can selectively activate JDE functions, but oftemtimes we have to get them all playing together. It is like going to the symphony - durng the 'warm - up" if only one instrument is playing it may sound like music, but if several instruments are warming up it is just noise. Only when all the instruments are playing together, in concert, do we get the real music the composer/arranger intended for us to hear.
I konw it is an iterative pain, but try the various combinations of the data field values, changing them one at a time, to really understand how they play together, and when they conflict.
Ifyou really want to maintain flexibility and soft commitment, the multi-location issues may be your option.
Finally, some questions for you - if multiple lot numbers of the same component go into you parent item, how does that impact lot tracking? Is the parent part lot controlled? If multiple parents are coming out of the WO, how do you distinguish which parents each lot of components went into?
I guess what I am asking is, "What is the big picture?" Piecemeal answers to isolated pieces seldom provide a satisfactory solution to an integrated whole solution. Often, they solve one problem only to introduce another problem elsewhere.