Due to a "serious injury," Bostaph was absent from the recording sessions for TESTAMENT's new album, "The Dark Roots Of Earth", which is scheduled for release on April 27, 2012 via Nuclear Blast Records. He was replaced in the studio by Gene "The Atomic Clock" Hoglan (ex-DARK ANGEL, ex-STRAPPING YOUNG LAD, FEAR FACTORY, DETHKLOK), who also sat behind the kit for select dates on TESTAMENT's recent North American tour with ANTHRAX.

"We just found our last week Paul Bostaph is not coming back to the band, he's starting his own new project and doing some things on his own," Billy told Terrorizer. "So we're actually going to be holding a couple of auditions with probably small group of drummers that we chose — we don't want to have a revolving drum stool, we have a new record we want a permanent drummer."

According to Chuck, the split with Bostaph is amicable. "We're still buddies," he said. "It's just that Paul feels at this point in his career he wants to be in a little more in control of the artistic creation of the songs and with his new project, they are all involved with that process whereas with our group, Eric [Peterson, guitar] is pretty much the main songwriter and that's just the way its been with us for 25 years."

LAMB OF GOD drummer Chris Adler plays on one track on "The Dark Roots Of Earth", which was helmed by veteran British producer Andy Sneap (MEGADETH, EXODUS, NEVERMORE, MACHINE HEAD, ARCH ENEMY).

Bostaph is currently focusing on BLACKGATES, the new East San Francisco Bay Area/New York metal outfit also featuring former ANTHRAX singer Dan Nelson, guitarist Jeremy Epp (THE VENTING MACHINE) and bassist Uriah Duffy (WHITESNAKE). The group was scheduled to enter the studio last month to start pre-production on its forthcoming debut album.

Bostaph previously stated about BLACKGATES's musical direction, "Our sound is drawn from all of our influences. Mostly, we don't want to be a thrash metal band, although we draw from that genre as well. There is something in our music for everyone. Heavy grooves, good hooks and Dan's killer pipes. I think we have an independent sound that will stand on its own."

In a September 9 interview with the "Metal Zone" host Nikki Blakk on the San Francisco, California radio station 107.7 The Bone, Bostaph stated about the "serious injury" which has forced him to sit out the recording sessions for TESTAMENT's new studio album and not be able to take part in any touring activities with the band, "I have a rehearsal studio of my own, and [back in March] I finished rehearsing and there was some equipment stacked around my drum set that, when I rehearse sometimes, I keep that studio a little dark… which is always good except for when you can't see what you are walking around. And I tripped over some stuff on the floor, fell, and subsequently, a couple of hours later, I had a lump on my wrist. I wasn't sure what it was and I went into physical therapy and the lump had caused tendonitis, so it kept me off the drum set for a while. And I just have had the lump removed. And what it turned out to be was I was born with what they call an extensor muscle that was attached to my index finger of my right hand, which is an extra muscle. They removed the muscle, the tendonitis is gone. Now I'm just recovering from the surgery, so as soon as I do that, I'll be back behind the kit again."

When asked about when fans can expect to see him back behind the hit, Paul said, "As soon as I'm ready to play. Basically, the tendonitis problem is gone; it was the result of the 'mini-me' that was in my wrist. The tendonitis that was caused from that is gone, but now they had to make an incision in my wrist, and because of that, anytime you get an incision, scar tissue develops after the surgery. So the scar issue is around all my tendons, and that has to be broken up through physical therapy, which is now happening. I'm getting my range of motion back, and after I get my range of motion back, then I get my strength back, and as soon as I get the confidence to start playing behind the kit, which is all repetitive motion. When you've got scar tissue surrounding tendons, and it's really tight and you try to push it, and you start doing any kind of a repetitive-motion exercise, which would be drumming, you could make whatever you were trying to fix, like, worse, or permanent. I've been getting timetables [from doctors] ever since I injured [my wrist], and they never turn out. The last time I saw my doctor, the doctor said, 'Take up the sticks whenever you're ready.' So as soon as I feel healthy enough and I'm confident that my wrist feels good, then I'll start picking up the sticks again and I'll start playing. I'm a very physical player, so there's only one way I know how to play, and if I can't do that, then that's just not playing drums to me. So I'm just gonna take my time."