Raids attunement

I'm new here to Outland, I read the infos thread and saw that the realm will be progressive starting from 2.1, I recall there was required attunement in 2.1 for:

Karazhan (The Master's Key). No longer necessary in the 2.4 to enter Krazhan but The gates to Karazhan will still require the Master's Key to be unlocked.

Serpentshrine Cavern (Quest: The Cudgel of Kar'desh), Tempest Keep (Quest Line finished by Trial of the Naaru: Magtheridon) completeing The Cudgel of Kar'desh and Trial of the Naaru: Magtheridon rewards the title: Champion of the Naaru.
In the 2.1.2 Tempest Keep and Serpentshrine Cavern no longer have a required attunement to enter.

Black Temple (Quest line finished by: A Distraction for Akama) and Mount Hyjal (Quest: The Vials of Eternity), Completing The Vials of Eternity and A Distraction for Akama rewards the title: Hand of A'dal.
In the 2.4 Black Temple and Mount Hyjal no longer have a required attunement to enter.

My question is how this is working here and how will it work when the server is progressing (launch of Zul Aman, Black Temple and Mount Hyjal).

In theory, they said it will work that when progressed, you will no longer need the "older" attunement.

As far as I know (<- emphasis on that part) the attunements will be handled in a blizz-like manner. By the time Sunwell is released, attunements won't be enforced at all.