Black Panther Different Suits In The Trailer Theory

I have a feeling the gangsters at night in the woods with Panther up in the tree is the opening sequence of the film. I say this mostly because it doesn't look like it matches anything else or seem relevant to what Killmonger is doing the rest of the film. It just seems like some bad guys surrounding Wakanda who would make for good cannon fodder.

Now I also think this is a flashback, and that is T'Chaka, not T'Challa. It seems a little old school, and I have this idea that the Civil War panther suit was T'Chaka's old suit.  That would make sense that T'Challa get's his own suit after becoming king, and is in the clearly modern day car chase sequence later in the trailer wearing it.