Exchange rate substitution for parked invoices

Hi Experts,

I have created a substitution for substituting the exchange rate than the one derived by standard SAP for rate type M.

This substitution works as expected for the invoices which are posted directly. However it does not work in case the invoice is parked first.

I went through OSS notes and came to know that substitution does not work for parked documents. It works only when the document is posted.

However we need to substitute even for parked invoices.

Can you please let me know if you had such requirement and is there any BTE/user exit/implicit enhancement/BADI or FM which can be used to meet this requirement?

Thank you in advance!

Best Regards

Aman Goel