On behalf of a user:

Since I need to follow emails or projects in different period of time, I would need to set up a reminder with multiple date at the same time.

For example I would like to send an email to my co-worker asking him to develop a prototype of a headphone. I know that the period of development will take about 4 months. I would like to set up the following reminders:

But instead of getting back the emails from my « sent » folder and create individual reminders every time, I would like to set up all these 5 reminders at the same time.

I know that followup.cc can do as they just need to add multiple email address « time and date » at the recipient under Bcc (3days@followup.cc; 3weeks@followup.cc; 2 months@followup.cc;….).