Tax finding in Project Invoice

Dear all, 

our company is in AUSTRIA, so the Supply Country is always AUSTRIA.

But we also export parts to Switzerland where we are registered. So we need to create a project invoice with swiss tax codes.

In IFS V10 Update 8 it was possible 

1. enter 2 Supply Countries for the default delivery address
   1. AUSTRIA with Tax Liability = EXAMPT: that we do not get an error message when we want to create the project invoice. This will be the Default Supply Country in the created project invoice
   2. SWITZERLAND with Tax Liability = TAX: that we can change the Supply Country and IFS find automatically the correct tax code

2. Existing Report Code: Which is “Taxable” with Swiss Tax code and Delivery Type 1 for the EXEMPT Supply Country AUSTRIA:

   

    

3. Created new project invoice with a Swiss Project 
   1. Supply Country = AUSTRIA
   2. Tax Code comes from the tax free tax code of the customer basic data 
4. We change the Supply country to SWITZERLAND and in Update 8 IFS changed automatically the Tax code to 058 CH UST 7,7% as you also see in the Report Code Detail.
   With Update 10 IFS do not update the tax code in the Project Invoice Lines.

How is the correct way to book invoices like this?

BR Linda