RDS Postgres stuck in Upgrading state

When your RDS Postgres instance is stuck in an "Upgrading" state for an extended period, such as the system update you mentioned, it can be a bit tricky since AWS doesn't directly offer a way to cancel an in-progress system update from the AWS Management Console. Here's what you can consider doing:

1. Wait It Out Often, the best course of action is patience. Database upgrades, especially major version updates, can take a significant amount of time, depending on your database's size and the upgrade's complexity. AWS is designed to manage these updates with minimal impact on availability, but they do take time.

2. AWS Support If the upgrade time seems unusually long or if you have a critical reason to revert the upgrade process, your best bet is to contact AWS Support for assistance. If you're on a support plan that allows for direct contact, this should be your next step:

Open a support ticket explaining your situation: include details like the instance identifier, the time the upgrade started, and any operational impact it's causing. AWS Support might not be able to cancel the upgrade. Still, they can provide insights into the upgrade's progress and estimated completion time or, in some rare cases, intervene in an unavailable way through the AWS Management Console.