We need the ability to update the NEXT recurring invoice in a series.

We only bill clients once a month, but sometimes we need to update the next month's recurring invoice to reflect a different charge than normal due to extra work being done that month that didn't reflect in the retainer.

How can we handle this? It looks like trying to edit a recurring invoice (even when clicking on the "Next Invoice" tab doesn't allow us to actually update the next invoice - only the entire series.