So somewhere during that 10 hour span, with the Tantive IV in increasing danger of being overtaken. Leia reached out to her father for ideas and he said "You're not too far from Tattoine... There's someone there who can help..."
That makes sense....
No -- in Bail's conversation with Mon Mothma in
Rogue One, he said that he was going to return to Alderaan, yet send a messenger to make contact with his exiled Jedi friend. Mothma said he should send someone he trusted, and he said "I'd trust her with my life." As the door closed, we heard him calling out to Captain Antilles to get his ship ready. So Leia was assigned to contact Kenobi before the Battle of Scarif happened. Then she got sidetracked along with the rest of the fleet when they went to Scarif to help Rogue One. Once she fled Scarif with the plans, she proceeded with her original mission to contact Kenobi, now with even greater urgency.
However by Endor, or even Hoth, it seems likely Kanan and Ezra are gone (dead or otherwise removed from the Light) due to Yoda's claim that Luke will be the last of the Jedi. And certainly by the time of TFA, if Luke is the only Jedi Master around.
Well, technically, Kanan isn't an official Jedi, only a lapsed Padawan. Although I guess he's closer to being an official Jedi than Luke ever was, since as Caleb Dume he trained for considerably longer than Luke did.
Also, Master is a higher rank of Jedi, isn't it? In ROTS, Anakin was upset about being allowed on the Council without being promoted to the rank of Master. I think I read once that the original intent was that there were at least two ranks of Jedi, Knight and Master. And the Masters were supposed to be more teachers than fighters, a distinction that got blurred in the prequels.
I'd been assuming that Kanan's blindness was going to be the excuse for why he was no longer active by the time of the movies, but Chirrut Imwe pretty much puts paid to that, doesn't he? As, of course, does Kanan himself in the current season.