You will get to keep 141 dollars per month that you received from Metlife(from the overpayment) and they will still owe you 141 a month since your SSDI pay is lesser than the LTD. Did you spend your backpay? They could withhold the 141 until they are paid in full. I'm on LTD also and need to do a yearly medical review with them to keep my benefits(100 per month). You will owe them for every month that you were paid backpay from SSDI.