Regular workflow post-functions run on transitions, but now you can schedule JMWE post-functions to run against issues returned by a JQL search. For example, you can automatically transition any issue escalated yet not addressed within your SLA threshold.
How it works:
In the Scheduled Actions library, set the schedule according to your requirements.
Then, select your parameters for issues you'd like to target with this automation.
Finally, create post-functions, for example, one to send a custom email, and another one to add a comment.
Use case: Send daily reminder email to assignees of issues that are "in progress"