Amazon RDS for PostgreSQL 11.x deprecation

Aurora Postgres:

Amazon RDS for PostgreSQL 11 will reach end of standard support on February 29, 2024. Refer this announcement.

Amazon RDS:

Based on Amazon RDS FAQs:

              When a minor version of a database engine is deprecated in Amazon RDS, we will provide a three (3) month period after the announcement before beginning automatic upgrades. 
              At the end of this period, all instances still running the deprecated minor version will be scheduled for automatic upgrade to the latest supported minor version during their scheduled maintenance windows.


            When a major version of the database engine is deprecated in Amazon RDS, we will provide a minimum six (6) month period after the announcement of a deprecation for you to initiate an upgrade to a supported major version. 
           At the end of this period, an automatic upgrade to the next major version will be applied to any instances still running the deprecated version during their scheduled maintenance windows.

On Release calendar for Amazon RDS for PostgreSQL, if you see section Release calendar for Amazon RDS for PostgreSQL major versions, following two points are important to note along with what I mentioned above:

             RDS for PostgreSQL major versions remain available at least until community end of life for the corresponding community version. You can use the following dates to plan your testing and upgrade cycles. 
             These dates represent the **earliest date** that an upgrade to a newer version might be required. If Amazon RDS extends support for an RDS for PostgreSQL version for longer than originally stated, we plan to update this table to reflect the later date.

             The end of standard support date for a major version is different from the end of standard support dates for its minor versions. The end of standard support dates for the available minor versions are listed Supported PostgreSQL versions on Amazon RDS.

Hope this helps, comment here if you have additional questions, happy to help.

Abhishek

Hello.
The document here does not give an exact date, but it states that support will end in November 2023.
https://docs.aws.amazon.com/AmazonRDS/latest/PostgreSQLReleaseNotes/postgresql-release-calendar.html