A discharge is the event that ends a loan's life with a lender, and for a broker it is the moment two things happen at once: the trail on that loan stops, and the lender checks the settlement date to see whether a clawback applies. On a commission statement it typically appears as a DISCHARGED payment type, sometimes with the last partial month of trail, sometimes with a negative upfront line a month or two later.
Not every discharge is a loss of the client. Some are property sales where the client will buy again, some are refinances the broker arranged to a better product, and some are full repayments by clients who have simply finished. What matters for the book is which loans are discharging and why, because a pattern of discharges to other lenders at months 13 to 26 is the signature of a book that is not being repriced.
The practical response is to track discharges monthly against the settlement date and the clawback schedule, so every one is either expected or investigated.