I know this question is old but there could be someone out there that may need help on it. I deployed a similar solution recently in one of my applications and thought I should share the script I used.
First, I needed to deploy an automated email sending script with PHPMailer and MySQL. The system is to send the emails daily to members based on their birth day and birth month. In course of my search, I came across this script from PHPMailer as seen via this link https://github.com/PHPMailer/PHPMailer/blob/master/examples/mailing_list.phps
I modified the script to suit my need. You can see my modified script via this link https://github.com/mnwuzor/BirthDay-Bulk-Email-Using-PHPMailer-MySQL.
To help in explaining the implementation, I created a YouTube video to explain what I did. You can what the video via this link https://www.youtube.com/watch?v=F3ruURrY_dk
Lastly, I know the question above do not require the use of CRON but for those that will need it, I use https://cron-job.org/en/ to schedule the process of sending the emails daily. You can watch this YouTube video to see the process of scheduling https://www.youtube.com/watch?v=8XuA_rc6lbY
Thank you guys for always helping out....