more over the time taken for SM/PM varies depending on the Depot too i guess...because for PM as they undergo A,B,I and POH too as part of PM, they will take more time but other than that , the tests that will be same and as long as it is matching with that report card thatthe secondary depot received from PM Depot.
and be it PM/SM, it will be done taking the train to Pitline and where there is no such provision, only Platform attention will be given !!!