I recorded all of the episodes during the Season 4 Preview Weekend, and I was rewatching all of them for the last few days. When I began to watch the episode "Clear" (the one when Morgan returns), a sign appeared that said "Erin, we tried for stone mountain -J". In my opinion, this is an obvious reference to the new characters Erin and Jack that are set to appear in Season 4 Episode 4 (I think?) What do you think? I know this one is pretty obvious, but I don't think anyone has metioned it before.