When Will and Saul enter Jack's apartment, the area of blood on the carpet where Jack was killed is considerably smaller than that shown after his murder.
The Helicopter landing on the ship was a very dangerous risk to a crash by approaching the pad tail first. Helicopters are very prone to losing Yaw Authority or Loss of Tail-rotor Effectiveness (LTE) when putting the tail first into the wind, this is never done unless absolutely avoidable. The moving ship and the winds incurred increase that risk significantly.
In a flashback, a Bell Longranger helicopter is seen landing on the ship in 1984 with the registration G-LVDC. That helicopter is still in service, but wasn't built until 1989.
The Helicopter landing on the ship Judgement Day at 36 minutes in has the registration code G-LVDC.
That helicopter registration was given out in 1989.
The caption says "North Atlantic Ocean 1984".
The caption says "North Atlantic Ocean 1984".