Is there an alert when using a course to create a waitlist

Summary:

In order to judge demand for an ILT offering, learners enroll into a course (with a no active offering status). When there is enough interest, offerings will be created. Is there an alert, or has anyone been successful in creating one, for when an offering is created for that course? We'd like an alert/notification to be sent to the learner on the course when a new offering has been created for a course so they can enroll in that offering.

Open to other suggestions on how to monitor demand for courses too. Thanks.