The core-module [Account Tax Cash Module] might fulfill your needs. Our “EUeR-Modul” (Ist-Versteuerung) on top on Cedric’s module move the “open” amounts to the accounts “schwebende Erträge” and “USt nicht fällig” until payed, analog Datev reporting (not knowing how they handle it internally). So, same result, more tradionally 
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