GL Date on F4111

We are running F470412 to process Inbound Invoices/Match to PO. After we process the document, if there is a variance, it creates F4111 record. The problem is that GL date on F4111 (and F43121) is different from F0911 thus docs show up on integrity reports and drives accounting crazy. I can't figure out where is the date on Cardex and Receiver file coming from as it does not match to ANY date on F4311 or F47 files. ANY ideas would be greatly appreciated.

OneWorld Xe, SP23,AS/400

update - it turns out that it picks up the G/L date from first document it encounters, such as old, unprocessed docs that are not marked as processed. Even more strange that it happens only for docs with variance where f4111 gets a record is created....