Web form to auto reminders via email/sms/voice

When someone fills out the form on: [login to view URL] 2 things should happen: 1) Thank you page loads automatically (which is happening now) [login to view URL] 2) The information needs to an app/SAAS that will automatically book the lead in for an appointment on Tuesday at 6 pm. If the form is filled after 6 pm on Tuesday, they will be booked for the following Tuesday at 6 pm. The SAAS/app needs to remind them at specific intervals via email/SMS/voice (preferably all 3 methods of contact) to come to the office at 6 pm on Tuesday. After this time, the funnel resets, and they do not get any more reminders. Please let me know what solution you will be using for this. ***I do NOT want to change to format of the web form. i.e. I want the 3 fields (name, email, number) to show on the main page. I do not want to give any calendar option on the web form. I want them to be booked automatically, without selecting time on a calendar. As soon as they press "Click here to get started", the thank you page should be loaded automatically. At the moment, the solution I think might work is to have the lead fill out the form and hit submit. In the back end, the information needs to be uploaded to google calendar (Tuesday 6 pm). After which AppToto (already linked to google calendar) will need to be configured to send out reminders. If you can do this, please let me know. If you have any better solution, I am open to it. Just let me know what solution you suggest other than the one I proposed above.