Hi Jim
Without you actually visiting the report, I can't see how this would be possible. Don't think a variable using "WhilePrintingRecords" to replace an existing date with an older date would work, but possibly. Maybe try using a formula field for the Document Date field that will do this, instead of focusing on the compile runtime variable.
Don't know Recurring Billing, but my comment would be if you can't reprint previously printed invoices from RB, then can't see how you would accomplish this with QR easily, if at all unless RB keeps a history file somewhere that you can pull invoice data from...thus being able to enter a date or date range at the "runtime" prompt, rather than focusing on the impossibility that the runtime variable will actually insert the date onto the report.
I wonder if a Windows-based macro utility would be able to do this for you? Following is a link to a site that specializes in Windows-based utilities. Haven't tried them, but this is the only suggestion I can come up with unless RB has another table that you can pull past invoices from.
www.windowware.com
"WinBatch Macro Scripting" from Wilson WindowWare.
I will look into further possibilities. Please let us know if you find another solution in the meantime.
Regards