HDG TRACK DEV IN A NON ADHERENCE TO AN ATC CLRNC INSTRUCTION.

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ON A CHKRIDE; WE JUST COMPLETED ONE APCH TO A FULL STOP (NOB 27R) AT OAK. WE REQUESTED IFR DEP RADAR VECTORS FOR ILS 27R. THE CTLR TOLD US TO TAXI BACK TO 27R FOR TKOF THEN CHANGED TO HOLD POS EXPECT 09L. HE THEN CAME BACK WITH 09L DEP BUT WITH DIFFERENT DEP CLRNC. A DIFFERENT CTLR CAME ON AND CLRED US FOR IMMEDIATE TKOF RWY 09L; AN ACFT WAS ON 1-2 MI FINAL FOR 27R. THE CTLR THEN CLRED THE ACFT ON FINAL TO LAND 27R AND ADVISED HIM DEPARTING ACFT WOULD BE TURNING SEBOUND. THE CTLR THEN TOLD US TO START TURN IMMEDIATELY. I TURNED R TO BE SE HDG. WELL; APPARENTLY OUR AMENDED CLRNC BACK ON THE GND WAS FOR A L TURN TO 080 DEGS ON DEP. I NEVER HEARD THAT. IN FACT; I MAY BE IN ERROR ABOUT THE 'SE TURN' REFERRING TO US. POSSIBLE CAUSES: BEING ON A CHKRIDE WITH FAA (PART 135 CHKRIDE). BEING IN A NEW AIRPLANE. BEING ISSUED 2-3 DIFFERENT SETS OF DEP INSTRUCTIONS THEN WHILE TRYING TO SORT THAT OUT BEING GIVEN AN IMMEDIATE DEP. IN RETROSPECT: I SHOULD HAVE DECLINED THE TKOF CLRNC. NOTE: THERE NEVER WAS A CONFLICT WITH ANY OTHER ACFT.