The band hasn't changed. Their music has changed over the years, true, but that's natural for any musician(s). Keeping the music exactly the same would just breed stagnation, and people would be here complaining about how every album sounds the same.
I'm not a big fan of 12:34, but no one can deny that it's the band's most technically ambitious album to date, and has easily the most complex and melodic compositions of any so far. Becoming a better musician and artist means experimenting and trying different things, regardless of whether or not a portion of your audience will enjoy it. If you don't like this or any album, then absorb it, take it for what it is, and view it as a stepping stone towards the continued greatness Authority Zero will achieve in the future.
And as for the band members themselves, I've been privilaged enough to be around the band for something like five or six years now, and hang out with them as friends and acquaintances. I can say that they're exactly the same honest, good natured and friendly people they've been since the day I met them.
Their live show hasn't changed much, either. There have been a few alterations here and there, but they've always been about putting on the biggest, fastest and rowdiest show as possible. Every time they get on stage they're throwing a party, and doing everything they can to make sure that everyone in attendance is having a great fucking time.
I think the issue here isn't with the band or it's music. It's about projecting an image on the band because they're popular and influential, and it's about an unfair level of expectation brought on by idolization. The original poster painted this picture in his head about what the band should be like, and it's entirely unfair to come here and complain about how they didn't match that picture perfectly.
So relax, take Authority Zero for what it is, and enjoy it!