The cabin theory
I saw some people questioning why the Dolls didn't attack earlier when Kenny visited the site earlier with Jim.
That is because the two didn't know of their existence.
Now that we know that nightmares can come true in the town (story with the man having nightmares of the dolls that later came true), is what I believe to be another clue.
Everyone at the lake site learns of the dolls existence with no real explanation yet. AND just before the group gets attacked in the cabin everyone is talking to each other except.......Ethan.
He's sleeping when Tabitha suddenly remembers some points.
He must be the cause for the attack as he could have gotten scared of their view earlier and now revisits that fear in a dream.
He also wakes up just before the attack!!!
He whole story of From and the changes of this cycle must be his doing. Or at least he must be unknowingly manipulating the place