This feature is very needed within Squarespace itself without an integration. Currently, using Email Automations, we can send an email to customers immediately after they make purchase, or schedule it to be a number of days or weeks out from that purchase. If there was an ability to schedule that automated email for a specific date and time, rather than a certain number of days out, that would make the Email Automations feature use-able for businesses that are selling live classes and need to send automated reminders on specific days. At the moment, the Email Automations feature is not useful for businesses selling live products for this reason.