Episode one of season one set the scene for the Temporal Leap series.
The Ariana was just moving into it's final stages of it's shakedown, the only thing they had left to test, was TIA and the temporal drive. Due to the technology being untested, standing orders were in place that it not be used until the specialist was aboard, who knew everything about the systems.
The First Officer of Ariana, Marion Dulmur, activated TIA. TIA quickly took control of Ariana and jumped the crew to the 16th April 2151, the day the NX-01 was launched.
Using the temporal communications array the Ariana is fitted with, Savage calls Echo Fleet command, but gets only a response from a Captain Data, who doesn't know of Echo Fleet, or Admiral Jackson, despite commanding Echo Fleet's Flag Ship, the USS Enterprise.
On their own, the crew have no other choice but to follow the mission orders TIA gave them.