Releases marked green are supported longer than 1 year, yellow are supported less than 1 year and red are no longer supported.
All versions get premier support, but no extended support. We recommend to switch to a new version as early as possible for fixing all bugs and getting all new features. Since APEX 18.1 there is no main or minor release any more, every release is getting the year with a counting number as version number. At the moment we are getting two releases for APEX in one year.

All information is given with no guarantee because of updates based on the original Oracle page.
Please refer to http://www.oracle.com/us/support/library/lifetime-support-technology-069183.pdf (PDF on page 24) for the original Information from Oracle.

More information regarding the Releases can be found here Overview Release Notes

The latest data update was made on 01.JANUARY .2024.