Do a search and you'll see that it is in fact a SAAMI spec round.
Where have you seen SAAMI spec for the 6.5x284?
I talked to Nosler a year ago when they started offering factory ammo about the pressures and specs`, and was told the tech that answered the phone didn`t have the numbers avialable at the moment but was sure they were CIP standard.
Norma has sponsored it in Europe but I don`t believe anyone has picked it up here and pressed SAAMI for admitance yet.