SPECULATION Things we may have missed from the last Teaser Trailer

What if the person that sneaks up behind Kylo is Luke??? He shows up to stop the attack and Kylo and Luke get into a fight but Kylo runs when he knows he can't win. Luke, tired and drained kneels down next to R2 to see the destruction he couldn't prevent. Then Kylo flys back to his ship and runs to the Vader helmet for "inspiration" to defeat Luke.

Of course, Luke only appearing in a flashback or in the end would have to be wrong for this to play out.

 

My first thought of who would be able to pull off the sneaking up from behind and elicit the response we see was also Luke.

And why couldn't it be? We have some timelines from MSW - it's not gospel. We know next to nothing about this movie - which I'm happy about.

 

I was just watching the trailer again and during the scene where Luke (presumably) is with R2, I can hear a distinct sound effect at the exact moment Luke puts his hand on R2, I hadn't noticed this before but now that I have the sound gives the effect that Luke is somehow using the force at this moment and his movements also seem to indicate some kind of concentration which I have previously interpreted as him just consoling R2 or showing some kind of affection towards him.
Am I reading too much into this? What could Luke be using the force for? Reading R2's memory? Is he angry and making everything shake? What do you guys think?

 

I think they are flying towards Maz's castle after the catapult weapon is used on it. It seems like the Resistance base is on the same planet as Maz is