Amazon RDS PostgreSQL minor versions end of standard support on March 31, 2025(All RDS is 16.6)

If you have already upgraded all your RDS instances to PostgreSQL 16.6 on January 1, 2025, you have taken the necessary action to address the end of standard support for older minor versions. PostgreSQL 16.6 is indeed the recommended version as of the information provided.

The repeated emails you're receiving are likely part of a general notification system that Amazon sends to all RDS PostgreSQL customers, regardless of their current version. These notifications are meant to ensure that no customers miss the important upgrade deadline.

Since you've already upgraded to 16.6, you should not experience any downtime related to this particular end-of-support notice. Your databases are running on a supported version that will continue to receive updates and patches.

However, to ensure everything is in order and to prevent any potential issues, you could take the following steps:

1. Double-check that all your RDS instances are indeed running PostgreSQL 16.6.
2. Verify that you have enabled Automatic Minor Version Upgrades for your RDS instances. This will ensure that your databases automatically receive future minor version updates within the 16.x series.
3. If you're still concerned, you can contact AWS Support for confirmation that your instances are properly updated and won't be affected by the March 31, 2025 deadline.

Remember that staying on the latest supported minor version is generally recommended for security and performance reasons. As long as you're on PostgreSQL 16.6, you shouldn't need to take any further action regarding this specific notice. Continue to monitor AWS communications for any future upgrade requirements or recommendations.
Sources
RDS Postgres version upgrade | AWS re:Post
Available PostgreSQL database versions - Amazon Relational Database Service