B757-200
Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Troubleshooting; Communication Breakdown
Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Human Factors; Company Policy
During preflight while attempting to load the flight plan into the FMS from the downlink; I received a FMS message that the flight plan was only partially loaded. After looking at the legs page; I realized that the fix preceding our destination was missing. I attempted to load the missing fix manually; but received a message that the fix was not in the database. I called our dispatcher and asked him to refile us with an alternate fix. A few minutes later I received an ACARS message from him stating that he refiled us using a different fix. I checked the new routing and it was 1 mile less than the original. I then requested and received our [departure clearance] which matched the new routing; and the rest of the flight was uneventful. During preflight preparation for our return to trip to ZZZ1 after our ZZZ layover; I noticed a second unsigned release for the flight in question. When we got to ZZZ1 I called the duty officer to explain what happened; and I requested to speak with the dispatcher. The dispatcher told me that he had sent a second release after he refiled us; but I was unaware of the new release so it was never signed. I was unaware that a new release was sent. [Operations]/flight crew coordination when a new release is issued after the original release is signed.
B757-200 Captain reported being unaware there was a new flight release for the flight resulting in an active flight release not being signed before departure.