Well, Timeless saved the best of its second season for last—that is, the last minute of the 2nd of a double episode. There will be spoilers ahead, so don't read on if you'd rather not know...
First, to set the context—the double episode, which was pretty much two separate episodes, tied together by the same sinews that tied together every episode this second second—began about 15 minutes late. Only appropriate for a time travel tale.
The first hour, about Harriet Tubman, was good enough. But the best story was saved for the second hour, and just got better and better. Jiya, taken prisoner by Rittenhouse, has escaped, and is living her life in 1880s Chinatown in San Francisco. She lets our team in the present know where she is—by a message in Klingon in an ad (I wonder if Lawrence M. Schoen was a consultant—look him up)—and concludes with a warning not to come find her. This is because she's seen Rufus dying in her vision, which she's now learned to scrutinize in its entirety.
Of course the team comes anyway. Before the episode is over, Lucy's mother and the Rittenhouse "genius" are (apparently) dead, Emma's in charge with a pregnant Jessica (with Wyatt's baby) as her second, and ... yes, Rufus is dead, too. In one of the best O'Henry-esque you-can't-defeat-fate twists of the season, Jiya manages to save Rufus from the death-by-knife in her vision, only to see him succumb shortly after to Emma's bullets.
Chinatown transforms Lucy, who tries to kill Emma, and fails only because her gun is out of bullets. Wyatt, back home in 2018, tells Lucy he loves her. It looks like all is lost -- mainly because, in the laws of time-travel that have been articulated so far in the series, you can't go back to a time you've already visited, so there's no way our team can go back to Chinatown and save Rufus a second time.
But apparently you can go back in time from some future date to where you are in 2018, and that's where the great last moment leaves us. Just when it seems that our team has run out of luck and hope if not time, an older version of Wyatt (bearded) and Lucy appear in a spiffier looking eyeball, i.e., time machine, and invite our current versions to go back with them to save Rufus....
I'd say that's a pretty powerful inducement for a third season. If NBC doesn't rise to the occasion, I'm sure some other network or streaming service will. Otherwise... well, you never know who may appear from the future as a convincer.