"Going into the studio" doesn't mean the same thing as it used to in the past. They're rarely all there at the same time. Travis is recording drums with Feldmann alone in the middle of the night, and Feldmann is at Hoppus' studio doing other stuff. The way the festival phrased the cancelation is proof they're wildly unhappy with this situation: "Unfortunately for the second year in a row, Blink-182 have cancelled their appearance at Bunbury." Bands don't need to divulge every detail behind every decision, but this is so hilariously unprofessional and, from the outside, looks like they just can't be bothered to fulfill the promise they made last year.