Before your term or holiday program starts and you are about to generate lesson invoices you should enter in you "Do Not Bill Periods".

The do not bill periods will ensure you clients are not billed for the incorrect fee calculation templates 

For example:

Term 1  -  1/1/2018 - 30/4/2018 (Learn to swim,General Billing, Squad, Term, Intensives) These could be your Fee calculation templates that all of your classes will fall under when Generating Invoices)

April Holidays  -  1/4/2018 - 14/4/2018 (Holidays)