Do I need to cancel my ED visa study if I leave Thailand before my extension?

The original poster has an ED visa and is considering leaving Thailand before their first extension on September 13. They inquired about whether they need to cancel their studies at the immigration office. Comments confirmed that as they are still under the initial 90-day stamp from their Non-ED visa, there is no need to cancel their studies, and they can leave without any additional procedures if they do not plan to return before the extension date.