We aren't. Did a full migration in August, 2015.

I watched PagerDuty leadership run out of the room when Amazon completely shit itself during a conference in 2011, and I heard a few months later that they'd signed up with Linode at some point after that. I could probably put two and two together there as a reliability strategy to back up against AWS failures.

Keep in mind Linode had a pretty good rep at the time. I wouldn't second guess them on the call, as I probably would have made it at the time, too. They didn't dig in or lock themselves in with debt, and bailed when the time was right, too.