To recreate: - Set MarkLostItemsAsReturned to ON for all cases, WhenLostChargeReplacementFee ON, WhenLostForgiveFine ON - Set you refund lost item value to refund lost fee and charge a new overdue fine - set a circ rule to charge $1 per day overdues - check out an item, setting its due date to 7 days ago - run the fines cron, see your $7 accruing fine - mark the item lost, confirm the $7 fine is forgiven - check the item in, backdating the checkin to 5 days ago - confirm your new fine is $2, but old_issues.returndate still shows the time at which this item was marked lost In this situation, I can't find anything in the data to explain why the fine is $2. That's the correct amount, given the actions, but if one stumbled on this patron after the fact one would have a hard time figuring out what happened.