If this is possible with RDS, that's huge. It's extremely frustrating to deal with spikes of transitory data into RDS and have to have the RDS disk space be sized to the maximum amount of space always-- it's a huge cost waste.
> Decreasing the size of an EBS volume is not supported. However, you can create a smaller volume and then migrate your data to it using application-level tools such as robocopy.
[1] - https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/consider...