IPV account for PO destination type Expense

Summary:

Need to change natural account on IPV account for PO destination type Expense

Content (please ensure you mask any confidential information):

Hello,

My topic concerns PO matched invoices with PO destination type Expense. For those distribution, IPV natural account must be deduced from Deliver to location.

I tried to change Natural account on Invoice price variance account by setting a segment rule on Natural account for Variance account in Purchasing TAD, but the custom rule does not apply (PO Charge account combination is created on invoice distribution, whatever Account rule in TAD).

How is it possible to customize IPV account generation rule ?