In the airport bookstand scene before the fateful flight, TJ suggests that Olive read "A Wrinkle In Time" by Madeleine L'Engle. The plot revolves around the same scenario of time travel as in this series.
The number for the safe deposit box is 6224 which is also the death date. In the movie Papillion (2017) the main character has hallucinations that include a safe code 6-2-24.
When the safe deposit box is opened the first item to catch the eye is a British medal; the 2002 Queen's Golden Jubilee Medal.