In Aus a "departure report" is used when an aircraft departs from an uncontrolled aerodrome. Eg "ABC, Departure Ayres Rock 02, tracking 040 degrees, climbing to FL250, estimating Alice Springs 34". VFR aircraft will use it on the area frequency to alert other aircraft to its presence. IFR aircraft, in addition, direct it to the appropriate centre who then enter the information into the computer for separation/traffic purposes.. . . .This may have been what he was after but then again maybe not. If it was at a controlled aerodrome surely he can tell what time you departed.