Top up payments are made to clients who are working (whether voluntarily or medically discharged from the ADF) are still required to be supported by medical certification to confirm that the condition continues to exist and that it continues to cause an Incapacity etc. In many cases these clients will be categorised as Chronically Incapacitated and the periods between certificates of Incapacity (or specialist review & report) may be extended up to 5 years.  If a SMR confirms the initial incapacity, then GP medical certification confirming ongoing incapacity is sufficient to extend for up to 5 years at a time if the delegate is satisfied with the GP report.