It doesn't matter, as it's not evidence for them choosing the "best case scenario" for themselves. The best case would of been them just keeping an overpayment,

It doesn't matter, as it's not evidence for them choosing the "best case scenario" for themselves. The best case would of been them just keeping an overpayment, and never refunding me anything. And besides, I have double checked the calculations before, and it's basically what they gave me (minus rounding cents to nearest dollar in each calculation).