Amazon RDS instances and the new Compute Savings Plans

I have a small single-instance deployment running on an EC2 instance which hosts both a web application and its database (MySQL). I've been looking to separate the deployment out into an EC2 instace for the web app and an RDS cluster for the database, and wanted to take advantage of the new AWS Savings Plans for both if possible.

My questions the are:

1. AWS Savings Plans seem to only apply to 'pure' compute EC2 instances, not to RDS instances as well. Can someone confirm or disprove this?
2. If Savings Plans did apply to RDS instances, is there a reason to not use them, and instead just use an Instance Reservation?

Since August 2020, AWS Savings Plans includes:

• Amazon EC2
• AWS Lambda
• AWS Fargate

They do not apply to Amazon RDS db instances. For those, you can continue to use Amazon RDS Reserved Instances.