Souza returned for a third stint last year, replacing former frontman Rob Dukes after years of bad feeling between the singer and guitarist Gary Holt. And Testament frontman Billy, who runs the Breaking Bands management firm, hints that the group were already thinking of ditching Dukes, who'd spent nine years with them.

Billy tells KTVU: "All we knew was that they were getting ready to do a new record and that possibly Rob might not be on this one. We thought, 'What do we do? Do we go out, start from scratch and get a new singer? Or do we maybe bring Zet back into the fold?

"We tossed it around and said, 'The thing that makes sense is Zet - he knows all the old material. He could step right in and nail the new record right away.'"