2250 — memory alpha

Multiple realities

(covers information from several alternate timelines)

Events

Captain Matthew Decker finishes his first five-year mission aboard the Constellation. (PIC: "The Star Gazer" commemorative plaque [1]^(X))

Robert April leaves the USS Enterprise as its commander for an appointment as Federation ambassador-at-large. (TAS: "The Counter-Clock Incident")
After serving as first officer under Captain April, Christopher Pike receives a promotion to captain and assumes command of the Enterprise. (DIS: "Brother")
Una Chin-Riley is made First officer. (SNW: "Ad Astra per Aspera" display graphic)

James T. Kirk is introduced to Gary Mitchell. Years later, they became friends when cadet Mitchell attended Lieutenant Kirk's philosophy class at Starfleet Academy. (TOS: "Where No Man Has Gone Before")
Spock graduates Starfleet Academy with a commission of ensign after enrolling there instead of the Vulcan Science Academy, against Sarek's wishes. (TOS: "Journey to Babel", "The Enterprise Incident"; SNW: "Among the Lotus Eaters"; display graphic)
Sarek becomes estranged from his son for the next eighteen years. (TOS: "Journey to Babel")

According to the Star Trek Chronology, April had ended his five-year mission aboard the USS Enterprise this year. This would later be confirmed by DIS: "Brother" on a viewscreen.