Delta sales order replication, per change to billing block, how?

Question

Issue: We want a change to sales order billing block field to trigger creation of a sales order delta replication IDoc, but having trouble getting that to work.
We added entry to table TBD62, for table VBAK, field FAKSK (billing block field), so change pointer would be created.
We have variant for delta replication set up on program ODTF_REPL_CO_SALESORDER_ITM.
A change to billing block field creates entry in table BDCP2, so change pointers are getting created successfully.
But running program RBDMIDOC for message type ODTF_COBJ_SALES_ORDER_ITEM, which should create the delta IDoc via the delta variant on program ODTF_REPL_CO_SALESORDER_ITM, does not create an IDoc.
If I change a partner on sales order, such as revenue manager or engagement manager, and then run RBDMIDOC for message type ODTF_COBJ_SALES_ORDER_ITEM, then the IDoc gets created.
So need help on how to set up so a change to billing block field, field VBAK-FAKSK, will trigger creation of sales order delta replication IDoc.  There seems to be more to it than just having change pointers get created in table BDCP2.
thanks,
Mark

Answer 1

I found out why IDoc not getting created for change to billing block on sales order.
SAP program ODTF_COBJ_SALES_ORDER_ITEM needs a fix.
Sales Order replication program ODTF_REPL_CO_SALESORDER_ITM has this piece of code:
    LOOP AT cp_so_it.
      ls_vbpos = cp_so_it-low.
      IF ls_vbpos-posnr IS INITIAL.
        APPEND ls_vbpos TO lt_vbeln.
      ELSE.
        APPEND ls_vbpos TO lt_vbpos.
      ENDIF.
    ENDLOOP.
For changes to table vbpa, for example, since vbpa key has posnr, ls_vbpos-posnr will have a value, and this code works.
But for changes to vbak, which doesn't have posnr in table key, ls_vbpos-posnr here is blank, not initial, and this code doesn't work.
eg. CDPOS-TABKEY/BDCP2-TABKEY for vbpa change might be something like "1300040000560000000RM", but for vbak something like "1300040000560".
This data feeds this IF statement above, which fails for changes to vbak data in triggering IDoc replication correctly.
ODTF_REPL_CO_SALESORDER_ITM should be modified to handle vbak change pointer data without the posnr field.