fringe series finale

I don't see how peter, Olivia, and etta, could still be together after history changed?

I wonder if both fringe divisions from earth alpha and earth beta still exist?

My take was that, rather than history being changed, they somehow managed to turn back time, spam. Right up until Peter had his daughter in his arms, I still thought it was all a dream. Interesting ending.

in the previous time line it was established that the earth became uninhabitable in the future. was that problem fixed when history changed?

does anybody know what the big metal cylinders that dug underground were?

I didn't get the ending either.

If sending the boy into the future prevents the future humans from travelling down the path of making the observers, thus preventing the invasion, then the observers wouldn't have existed in the first place, let alone back when Walter was in the ice with Alternate Peter, thus nobody to save them.... thus, no Peter for that ending of the show..... thus no show in the first place.

Either that or I seriously missed something in my Star Trek Time Line Education Classes.

Maybe they skipped ahead and forgot to tell you?