I didn't read all the points carefully, but regarding #9 one needs to see https://aws.amazon.com/ec2/faqs/ https://aws.amazon.com/ec2/faqs/ You can modify exis

I didn't read all the points carefully, but regarding #9 one needs to see https://aws.amazon.com/ec2/faqs/ https://aws.amazon.com/ec2/faqs/ You can modify existing Reserved Instances via the Amazon EC2 Console or by using the ModifyReservedInstances API call. In both cases, the reservation must match the following attributes of the running instance you want to cover: Availability Zone (e.g., us-east-1a) Instance type (e.g., m3.large) Platform (e.g., Linux/UNIX (Amazon VPC)) Tenancy (e.g., default)