Basically, you need to create a CRON.
You can do this in WP, however, if your site does not get a lot of traffic the notifications may not go out on time as it requires a page on the site to be loaded to trigger the cron https://www.advancedcustomfields.com/resources/acf_form/
CRON jobs can also, usually, be set up on hour hosting to run at specific interval https://www.siteground.com/tutorials/wordpress/real-cron-job/ and these are more reliable.
In the code you’d need to do queries to find all of the notes that need to be sent and then send the emails.
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