I send emails using PHPMailer, vie a foreach loop, using SES SMTP credentials. Batches of about 20-30 every few days.
This has been running for a number of years on php5.6
Recently, I upgraded to php7.4.
Since then, the same php script run, with no errors and all emails are delivered. However, I've noticed that I now only receive a SNS delivery receipt email for the first email sent in the loop, and SES dashboard only shows 1 email as being sent.
I'm not quite sure what would cause this behaviour and weather I should be worried or not.
Any input appreciated, thank you.