Someone replied that options 6 and 7 both specify a refund of the overpayment, but that is not correct.

Option 6 says "Apply entire refund, estimates if necessary"

Option 7 says, "Apply entire refund, no estimates"

There is no option to "Refund entire overpayment"

I am using option 7, and also specifying in the line below ("Amount to apply to 2020) that 0 is to be applied, but ProConnect is still applying 100% of the overpayment to 2020, and refunding none.