Conversation so far:
When did the lineup change?
Hoppus and Barker decided to continue on without DeLonge, and enlisted Alkaline Trio vocalist/guitarist Matt Skiba to "fill in.
HOw long was Skiba with them?
Hoppus and Skiba had been wanting to work together musically for several years, so he was the first and only person considered for the role.

Question: Have they done any tours with him?
Self-contained rewrite: Have Blink-182 done any tours with Skiba?