Kyle Reese volunteers to travel back in time to save John Connor's mother Sarah from termination. Arriving in 1984 Reese learned that Sarah had been under the protection of a reprogrammed Terminator since 1974. After destroying two Terminators in 1984, Reese and Sarah traveled forward in time to 2017 to destroy Skynet, which was being protected by a Terminator/Human hybrid John Connor.
1997
1997, August 29th
Skynet launched pre-emptive nuclear attacks against the worlds leading military powers, which combined with the inevitable retaliatory nuclear attacks resulted in the death of 3 billion human lives and blanketed most of the developed world in nuclear fallout - Judgment Day.
[Source - Terminator: Genisys]
2017
2017, August 29th
John Connor rescued a 13-year-old Kyle Reese from termination in a Los Angeles sewage drain.
[Source - Terminator: Genisys]
Because the same actor (Bryant Prince) is used to portray young Kyle Reese in both the mentioned scene and in the latter part of the movie set in 2017, together with Reese's "new memories" of his childhood home, which the character later visits on August 29th, 2017, said date has been used for the above scene. This is similar to how the Future War and Future Coda scenes in Terminator 2: Judgment Day were originally intended to be alternate versions of the same date.
2029
2029, July 11th
A series 800, Cyberdyne Systems model 101 "Terminator" Infiltrator Unit was sent back in time to May 12th, 1984 using Skynet's Time Displacement Equipment. Shortly afterward, Sergeant Kyle Reese (DN 38416) volunteered to follow the Terminator back in time to protect Sarah Connor. As Reese is being sent back in time Skynet, in the form of the T-5000 attacked John Connor.
[Source - Terminator: Genisys, Terminator 2: Judgment Day, Revised Final Shooting Script]
1974
A series 1000 "Terminator" Infiltrator Unit and a reprogrammed series 800 Cyberdyne Systems model 101 "Terminator" Infiltrator Unit arrived via chrono-spheres; date unknown. The T-1000 located Sarah J Connor at the "Big Bear" cabin before killing both of her parents, but before the T-1000 could terminate Sarah she was rescued by the reprogrammed Terminator.
[Source - Terminator Genisys]
1984
1984, May 12th01:52am
A series 800, Cyberdyne Systems model 101 "Terminator" Infiltrator Unit arrived via a chrono-sphere at Griffin Park Observatory, Los Angeles, California. Shortly afterward, Kyle Reese arrived via another chrono-sphere in a Los Angeles alleyway.
[Source - Terminator: Genisys]
1984, May 12th
The Terminator was confronted by the reprogrammed Terminator before it was incapacitated by a high-caliber sniper rifle fired by Sarah Connor. Reese was pursued into a closed Way-Mart store by the T-1000 before being rescued by Sarah Connor, who revealed that she knew all about the future war, Terminators and her son John's future as the leader of the Human Resistance. After Sarah, Reese and the reprogrammed Terminator destroyed the remains of the Terminator and defeated the T-1000, the reprogrammed Terminator used the other Terminators Neural Network Processor to power a crudely assembled TDE, sending Reese and Sarah forward in time to August 28th, 2017.
2017
2017, August 28th
Reese and Sarah arrived via a chrono-sphere in the middle of a Los Angeles highway before being arrested by the LAPD. While being treated for minor injuries in a nearby hospital Reese and Sarah escaped with the assistance of John Connor, who had previously traveled back in time to 2014. The reprogrammed Terminator attacked John revealing him to be a Human/Terminator hybrid, a T-3000. John pursued them in a high-speed pursuit which ended with Sarah, Reese and the reprogrammed Terminator being arrested. Breaking free they were pursued by John in a helicopter chase to Cyberdyne Systems headquarters, within which they attempted to destroy Skynet (which was masquerading as Genisys, a multiplatform application). However, they were thwarted by John before he and Cyberdyne Systems were destroyed by the reprogrammed Terminator. Buried beneath the rubble of the building Sarah and Reese were rescued by the reprogrammed Terminator, who had been upgraded with a sheath of mimetic poly-alloy.
[Source - Terminator: Genisys]
2017, August 29th
Visiting Reese's old family home Sarah and Reese met his younger self, and as a precaution urged him to recite that Genisys was Skynet to himself. Beneath the rubble of the Cyberdyne Systems headquarters, in a hardened bunker Skynet was revealed to still be active.
[Source - Terminator: Genisys]
