Hold Remainder function creates two additional transactions in the Pro forma invoice

HI,

We have created an employee time card and created a Pro forma invoice.
In Pro forma Invoice we have changed the Qty to invoice as less amount.

We changed the line status to "Hold Remainder".

When we ran the next billing, the system created 2nd invoice lines as we expected.
However, the remaining qty(From the Previous bill) relevant lines have been duplicated.

Could we stop this duplication? Attached is the screenshot.