Each journal has it’s reference number field under the root Sales Journal > Sub Journals in which you can select your next reference number.
Each journal has its own window select Trade Information where you can specify the PST rate and the account to post the PST amount to.
Could you not add a Consumption Sales Journal and add the invoices there? Are these duplicate invoices? If they are, use a TAG on the Consumption Journal to retrieve the consumptioninformation require.
I do not understand why you need to move invoices and calculate PST manually.
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