Agree. They didn't have a producer, probably couldn't afford one. It's a shame.
As far as what they're teasing... it's probably just an anniversary of one of their albums. Or maybe a one-off show somewhere.
I think they intended to self-produce it, and I think it worked out really well for them. They have their own studio and all, so they probably figured why spend them money when we can do it ourselves, ya know?