It’s worth learning the AWS CLI and jq in order to do one-off batch operations to EC2 instances. I needed to start a group of stopped instances that all had the same name. Here’s the one-liner:
aws ec2 describe-instances --filters \ Name=tag:Name,Values="name goes here" | \ jq ".Reservations[].Instances[].InstanceId" -r | \ xargs aws ec2 start-instances --instance-ids
Lorin's Tech Blog 