I would expect that the whole first order vs resistance thing is going to be a small background story in the last film.
Lets look at it.
The Resistance fleet is gone, nobody came to help them, they have maybe a dozen people or so left. Their leadership is gone except for Poe and Finn.
Its not much better on the First Order side of things.
When the Supremecy was blown up, that was their capital world, and their main manufacturing facility and training center. Most of their fleet was pretty much shattered. Their leadership is gutted, Snoke dead, Phasma who was actually a member of the leadership of the first order dead. They have Hux who's generally stupid and Ren left.
Basically the next movie is going to probably be about the end of the whole dark versus light battle within the force. I have a feeling that
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