Here's an easy way to manage your instructors in exchange for a subscription.

In the profile of a member, it is possible to apply a credit to the account manually, via the tab "General"> "General information" in the profile of your instructor/member.

Count the number of hours that your instructor has done during the month and then apply it to his profile in the form of a credit which will be deducted as his payments are due.

This is a simple and easy way not to lose count of the hours completed by an instructor.