Delta init for 0CO_OM_OPA_6 doubt

Hi

To test delta init I sterted 0CO_OM_OPA_6 extractors twice at the same time.

Both with the same restrictions: period from 2009008 to 2099016.

First like Delta init. Second like Full load.

Delta load returned about 4000 record less then Full load.

System is active. I am not able to stop posting CO documents from outside systems to R3.

Somebody is able to expalin me why I got less records in delta load?

THX

Adam