This question is not a duplicate of the linked post as I want to know support time for only other Ubuntu flavors.
now running the command you can see that packages related to desktop environment are supported for 3 years and those system related are supported for 5 years.
As Ubuntu flavors are based on some other desktop environment like lubuntu is based on LXDE,these desktop environments are not in control of canonical which had made Ubuntu.but unity which is default desktop environment of the Ubuntu is made by canonical and thus they are in full control of the unity desktop environment,thus they provide 5 years of support to maximum packages.
You may still get updates for a lot of other packages installed in your Ubuntu, because they are part of official repositories.
to get a list of all packages and their support status:
You have 12 packages (0.6%) supported until May 2022 (5y) You have 1393 packages (71.5%) supported until April 2021 (5y) You have 327 packages (16.8%) supported until April 2019 (3y)
I'm running "xenial", however as you see I've got some packages with 3 years support too.