Releases marked green are supported longer than 1 year, yellow are supported less than 1 year and red are no longer supported.
This overview is only refering to premier support and not extended support. We recommend to switch to a new version as early as possible to a long term release.

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 4) for the original Information from Oracle.

More information regarding the Releases can be found here Release Schedule of Current Database Releases

Regarding future releases they are only planned. My last information is based on the DOAG 2020 conference. Look into this tweet.

The latest data update was made on 23.NOVEMBER .2022.