Can I use Heroku's cedar-14 stack from April 2019?

Expired support in this industry is generally
- This does not mean that it will become unavailable
- You can keep using it, but it's your responsibility to use it
- The provider will not take care of bugs, vulnerabilities or other inconveniences
This means that the provider waives responsibility.

In fact, Win XP and Win Vista are not "unavailable" even now that they are no longer supported (although Heroku may not be)."Whether or not ""practical"" is another matter.For example, Win XP cannot view the current https site properly because certificate updates and SSL/TLS support updates are not made, and the safety is 0.

Since the Ceder-14 is already deprecated, we strongly recommend that you test it with Heroku-18 and upgrade it now.

In conclusion, The application will no longer be available from April 2019.

Cedar-14 is now degraded page states:

After April 2019 builds for apps running on Cedar-14 will no longer work.

After April 2019, the build of the app running on Cedar-14 will no longer work (I'm sorry, but I don't know exactly what this build means because I don't use Heroku).

In addition, the Stack Update Policy page states:

Old stacks are retired when they are no longer receiving support from Canonical (5 years after Canonical introduces that LTS release). Heroku will notify users with apps on old stacks before they are retired. Notifications are in the form of Changelog entries and direct emails to owners and collaborators on apps running on stacks that are about to be retired.

Stacks that are no longer supported will be retire.

Also, although it is a slightly older document, Cedar-14 now Generally Available contains the following (emphasized by respondents):

Stacks cannot live forever – packages and distro versions are deprecated or stop receiving security updates. With Cedar-14 GA, we’re also announcing the deprecation of the classic Cedar runtime stack: A year from now, on November 4th, 2015, the classic Cedar stack will be retired and any apps that have not been migrated to Cedar-14 will stop running. You must migrate all apps to Cedar-14 beforeturn to prevent disruption in availability.In the coming year, we will keep the old Cedar stack image patched and updated.

In the case of the classic Cedar stack, which was discontinued in November 2015, it was clearly stated that the app would stop working at that time.

Based on the above, we believe that the application will no longer be available in April 2019.