Why the Ubuntu 16.04 LTS is till 2020-2022 and not just 2022?
What is the reason for choosing to stop LTS inside a range and not a specific year?
ubuntu-support-status shows that the majority of the packages on my Ubuntu 16.04 are supported until April, 2021 which is the same as the Ubuntu 16.04 release end of life which is listed at the official Ubuntu release cycle | Ubuntu website. As you can see on the chart on the linked website (part of which is shown below), Ubuntu 12.04 LTS has already been an end of life release since April, 2017, but its security maintenance has been extended for an additional 3 years until April, 2020 for Ubuntu Advantage customers, and the security maintenance of Ubuntu 14.04 has been extended for an additional 3 years until April, 2022.
The next Extended Security Maintenance (ESM) release after 14.04 will be Ubuntu 16.04.
At OpenStack Summit held on November, 2018 Canonical and Ubuntu founder Mark Shuttleworth said in a keynote that Ubuntu 18.04 Extended Security Maintenance support lifespan would extend Ubuntu 18.04 support from 5 years to 10 years.
There are some packages installed on my system that are supported only until April, 2019 and other packages that are supported until January, 2023, however like the other Ubuntu LTS releases Ubuntu 16.04 LTS is supported for 5 years after its release date.
Ubuntu Core, with an image size of 260MB, is the smallest Ubuntu release to date. This makes it ideal both for IoT devices and cloud containers. Ubuntu Core 18 is based on Ubuntu 18.04, and is supported for 10 years. A new release of Ubuntu Core is released every 2 years on even numbered years (2016, 2018, etc.).