B767-300 and 300 ER
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Communication Breakdown
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural MEL / CDL; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Procedure; MEL; Manuals; Logbook Entry; Aircraft
The crew and I operated the aircraft from ZZZ to ZZZ1. The aircraft had a total of six MEL items; most notably 29-XX-XX and 24-XX-XX-XXX; Air Driven Pump and Hydraulic Motor Generator Valves respectively. 24-XX-XX-XXX is a Cat A deferral and allowed us to operate under ETOPS with the APU running. This MEL had an expiration date of [date]. My crew and I took note of this because this is the same aircraft we were to operate back to ZZZ the next day. Our arrival time in ZZZ was scheduled after XA00Z; so if the MEL was not cleared; we would not be able to operate ZZZ1 to ZZZ. Upon our arrival to the aircraft the next day; I reviewed the logbook. MEL 24-XX-XX-XXX was not cleared; but 'Amended' to MEL 24-XX-XX-XXX which is a Cat C item; thus allowing the aircraft to continue flying. The on board mechanic was insistent that this 'Amendment' was legal and was adamant on getting the aircraft to ZZZ2 were it was scheduled to undergo maintenance. As a crew we weren't sure of the legality of this unusual MEL extension; as only Cat B and C MEL's are extendable with FSDO approval. We decided to contact Chief Pilot for his opinion and approval to depart. [Chief Pilot] did indeed give us permission to depart to ZZZ under the current state of the DDG.This; to me; seems to be a misuse and manipulation of the DDG program in order to prevent an aircraft from being grounded and allowing it to keep flying. In this case; aircraft was scheduled to be in ZZZ2 a couple days later where it was scheduled to undergo maintenance. This MEL 'Amendment'; in my opinion; was a way to extend an MEL item that wasn't legally extendable.
B767 Captain reported a lack of consensus in an MEL change.