11.5.10.2 Payables Open Interface - importing tax lines and invoice validation

Hi All,

I have a scenario whereby Automatic Tax Calculation is on in Payables at line level (and must remain as such for manual invoice on the Invoice Workbench) but we have an external system sending invoices through the Open Interface with tax lines provided.

This is causing the invoices to go on DIST VARIANCE and TAX_AMOUNT_RANGE holds when the invoices are validated as the system is calculating tax on top of the tax line provided (I understand that this is because the ap_invoice_distributions_all.calculate_Tax_flag is 'N' by default).  I have tried  setting it to 'Y' before invoice validation and this works, but then it doesn't check to see that the tax amount passed is within tolerance.