Saw Gerrara is bald in flashbacks and bearded in the “present”, therefore I believe most of the early trailer shots are from a cut that has some Jyn in training and/or her abandonment. The dialog “What will you do when they catch you? What will you do if they break you? If you continue to fight, what will you become?” sounds like training or his final speech as he leaves her behind.
I agree this sounds like exactly what you say - but then Jyn would’ve been to Jedha previously, as that’s the same room in which they meet later. So…not sure what to make of that?