We recently upgraded a customer's system from 8.2 to 8.4. They've been using a tax rule (NL > Settings > Tax Rules) with code 99, type "Reversed", and have set this against VAT code 50 on flip B of the VAT Codes screen. VAT Code 50 is set up at 19%.
This allows a purchase invoice to be posted using VAT code 50. If the row sum was 1000, the calculated VAT is 190, however because of the reverse VAT tax rule, the TOTAL field should be 1000, not 1190. When OKed, the NL transaction does a reverse VAT posting.
In 8.4, it does not let you save the purchase invoice with this scenario. It says "Transaction out of balance". I have compared the procedure VISumup between 8.2 and 8.4 source code, and can see that the code relevant to tax rules has been removed from 8.4, and therefore the purchase invoice fails the balance check. Is there a reason why this was removed? Is there a different way to do this in 8.4? Or is it simply a bug?