VAT RETURN TAXE DATE

Hello dear Experts and SAP community, I am currently working on a blocking point in SAP BUSINESS BY DESIGN and i am likely to need your return of experience on this question:

In Morocco, we use « Differ Tax » because VAT is filied only after payment. Tax administration consider payment according to bank statement and not posting date. How could we differ tax return until date of bank reconciliation ?

Thanks in advance,

Best regards