If you're using the GoCentral Online Appointment Scheduling you can already have the attendees sent either a text or email reminder or both @Tattooedgirl78. When you are setting up your appointment or service I believe the "Remind customers of upcoming appointments and events." is under a section called Customer Reminders in Step 3. If you have already setup your appointments you can find the notification section under Settings in the Notifications tab. You can additionally choose the notice timing.
Check out Add Online Appointments section. Online Appointments is only available for Business Plus or eCommerce plans. I've found that it works great and there are a lot of settings for availability, location, time zone... I hope that helps?
...turns out that my two cents is worth less or more depending on the current exchange rate.
roy darling *my posts seem a lot shorter in my head