Change effective on 03 May 2018
Cedar-14, our stack based on Ubuntu 14.04, is now deprecated. Your apps will continue to run and builds will continue to work, but we suggest you migrate your apps to the latest stack.
Cedar-14 will be supported on the platform until April 2019. After April 2019 builds for apps running on Cedar-14 will no longer work.
Update 2019-05-01: The Cedar-14 end-of-life timeline has has been revised.