Because credits are not journalized in the BasicBooks General Ledger until they have been applied credits may be deleted at any time regardless of whether they have been applied or not. Selecting Delete Credits provides the option to select and delete any single credit or, you may elect to delete all closed credits,
There is no rule for when you should delete credits. However, closed credits will continue to appear on lists and reports until such time as you delete them, This can cause reports to look cluttered. So, it is a matter of preference when to delete closed credits.