Does a single EC2 Reserved Instances allow for multiple EC2 instances for a partial hour

Question

I understand that EC2 Reserved Instances are a billing feature.

I purchase 1 Reserved Instance for an m5.2xlarge in AZa and pay all up-front for the year.

Let's say I run 2 m5.2xlarge instances in AZa for the first 30 minutes fo the hour, then terminate both for the next 30 minutes.

Will I incur any on-demand costs for that hour, or will my single RI cover the EC2 costs for that hour?

Answer 1

According to: Announcing Amazon EC2 per second billing

With Reserved Instances usage you can launch, use, and terminate multiple instances within an hour and get the Reserved Instance Benefit for all of the instances. Bills will now show times in decimal form instead of in minutes and seconds.

So you should not incur any on-demand charges.

Answer 2

@maafk Yes, it will cost for that hour. because you have reserved a single instance. Also, there is an hourly billing.