"From a personal point of view, there were doubts [about our future, but] my friends' lives come before the band. As much as the band is part of our lives . . . we have to be healthy – mentally and physically – and what we do on stage is not easy, it carries a lot of responsibility, and it carries a lot of physical stress and mental stress. At this point, [Green Day] is held to a higher bar than we would have been a long time ago."

Dirnt says that before Armstrong's meltdown, Green Day hadn't really stopped for 20 years. "We hadn't taken a vacation, hadn't looked up, hadn't done anything that wasn't writing music and touring. When you're working that hard, there's a lot of down time on the road. You can drink too much or get into sleeping pills or whatever, but at some point, you have to step up and make sure the person that you are is the [best] part of you."

"It's more appealing to me [than a festival where] there's a techno tent next to me while I'm trying to play," he says. "I'm all for diversity, but I'm not really into stupidity; sometimes shows are booked kinda stupid. A lot of fans don't want [that].

"Soundwave has its own identity, it's like a [rock] mecca to go to."

Dirnt wasn't sure if Green Day would play their huge breakthrough album, Dookie, which turns 20 in 2014, as they did at the Reading and Leeds festivals last month. At Reading, the band covered the Ramones' Blitzkreig Bop and AC/DC's Highway to Hell – which they could do again.

"It's an anthem and that's what it's all about. That's us tipping our hat [to AC/DC]," Dirnt says of the band he credits with being one of his two formative music experiences. "In 10th grade I remember trading my bicycle for a weekend to borrow the cassette tape of Back in Black . . . and that was awesome."