Def Leppard completed a run of four casino shows in Nevada and California last night in Temecula, California. Trixter‘s Steve Brown stood in for guitarist Vivian Campbell, who’s still undergoing treatments for Hodgkins lymphoma.

Singer Joe Elliott told Billboard he expects the shows with Brown will “just be a footnote in Lep history, and everything’ll get back to normal, God willing, next year.”

The band is gearing up for a big 2015. He says they’ve got about 15 new songs “in various, different degrees of being finished.” They “only set out to write three or four songs in February” but ended up with 12. Elliott’s “still trying to figure out how and why” they were suddenly so prolific, but thinks “one of the whys is we haven’t really written since 2007, 2008, so we’re backed up.”

Elliott says the hope is that Campbell will be done with the current round of cancer treatments mid-month and will be involved in finishing the new material next year.