User blog comment:TheDoctor230/Flashpoint Theory/@comment-3221148-20160528212804

According to Thawne, the white-symbol Barry he fought was the one from his original timeline, so it's basically a time remnant from the timeline where Barry became the Flash in 2020.

Earlier, we assumed that Barry-2020 was the one to warn Barry-2015 not to approach. And, who knows, maybe it originally was just like that. But, in S2 finale, we see Barry-2020 fight Thawne, then race out of the building saving Barry-2000, only for Barry-2016 to knock Thawne out and save his mother. However, while earlier we saw a white-symbol Barry stopping Barry-2015, this time, it doesn't happen, and Barry-2015 dissipates into thin air after seeing that Nora Allen is already saved.

So, in S2 finale, there were 4 Barries, 3 Flashes among them (2020s, 2015 and 2016 versions). I think that the Flashpoint will end with Barry-2016 stopping himself, then stopping the 2015 version, with that scene from S1 finale, when white-symbol Barry holds his hand to stop the red-symbol one, re-enacted.