Looking like this show may be 3+ timelines all mixed up. Bernard appears to be an exact copy of Arnold, so some of what we're seeing is actually Arnold working with Delores, and the rest is Bernard. Looks
Like William really is the MIB.... so ok I guess. Delores meanwhile is all over the friggin map. It's all very clever in a way, but it's also getting pretty tiresome.
The problem, for me, is that when there are essentially no firm rules to this show (in this world pretty much anything is technologically possible - including making exact copies of people - and any given scene can be realtime or flashback), the writers can do whatever the eff they want. And if the writers can go any direction they please, it's not that fun to try to solve the puzzle. It more like "ok what crazy crap that doesn't make much sense will we get this week?"