Mini application de coaching email

Program email application.

We want to developp a coach program emailing application.

1. This app will collect users information from Database / Mailing list API (not defined yet, could be Mysql or MAilchimp list.
2. Once in base, each user will receive a daily program of emails. +-30 emails with defined content, and simple personalisation (name, last name).
3. Program starts 1st march and last for a month.
4. If a user get registrerd last day of march, he will still get his programm fully (Goes up to end of april then). Maximum lenght of operation is 2 month.
5. Delivrability is a must, use of seindinblue/Mailchimp API for sending is prefered, please propose any solution. (Sending to France)

This project has to be quoted for those tasks only (site collecting data is made by another agency).
Advise on best Email sending solution (server, API, any service…)

Thanks