How to automate emails based on [Date Received] and at different intervals thereafter?

An email only triggers when a single or multi record operation has occurred. there is no trigger for something becoming true via formula.  

Solutions I have seen in the past used a server side cron script to query the records that would need the next email sent out, and edit those records using the api individually in a loop to send single record notifications, or in mass for multi record operations. 

Now... automations based on a daily schedule, running a Table to Table import if date X = today, to set a checkbox to true for triggering the next email event should work. This will trigger a Multi record email notification however. 

For sending a single record notification out one at a time to each customer, you may need a server side script to run on a schedule. 

I have solved this requirement using a Table to Table import and 2 Automations using a formulaic relationship to a parameter table. I am now able to send single record notifications for many records on a daily basis by triggering a looping automation. If you are interested, I can see if I can document this for you.