Dears Specs !
I have some investigation regarding VBAP, beacuse I can see less Document Item in VA03 transaction then it is in VBAP tables.
It was quite obviouse that the missing items has been deleted and in the source code of VA03 I can see that there is a XVBAP table with the column UPDKZ where all the 'D' (deleted ) items has been removed.
What I could not figure out where XVBAP takes this information (what is the source table of XVBAP)