Agora é possível automatizar o snapshot a partir do console da AWS usando as regras do CloudWatch.
Conforme explicado na documentação do AWS CloudWatch
Create a rule that takes snapshots on a schedule. You can use a rate expression or a cron expression to specify the schedule. For more information, see Schedule Expressions for Rules.
To create a rule
1. Open the CloudWatch console at https://console.aws.amazon.com/cloudwatch/.
2. In the navigation pane, choose Events, Create rule.
3. For Event Source, do the following:
a. Choose Schedule.
b. Choose Fixed rate of and specify the schedule interval (for example, 5 minutes). Alternatively, choose Cron expression and specify a cron expression (for example, every 15 minutes Monday through Friday, starting at the current time).
4. For Targets, choose Add target and then select EC2 Create Snapshot API call.
5. For Volume ID, choose an EBS volume.
6. Choose Configure details.
7. For Rule definition, type a name and description for the rule.
8. For AWS permissions, choose the option to create a new role. This opens the IAM console in a new tab. The new role grants the built-in target permissions to access resources on your behalf. Choose Allow. The tab with the IAM window closes.
9. Choose Create rule.