Try something like this:

Local lcInvoice_ID

* Save the value of the Invoice_ID as lcInvoice_ID
* If you need help doing this let me know.
lcInvoice_ID = lcInvoice_ID


Select Invoice Detail

Scan
Replace Product.UseSeason with m.currentseason for InvoiceDetail.Invoice_ID = lcInvoice_ID
EndScan

Let me know how it goes. I have to go home now.

Tom