Whatever you do, don't do this.
- a sleep for 300s to avoid full 24 hour rollover (lol)
- sleep 1d instead of cron; so at random times emails will be sent out or they won't at all
- this is a laravel project, there's a thing called task scheduling: https://laravel.com/docs/5.8/...

Git blame: https://github.com/invoiceninja/...

The actual core project docs at least tell you to setup a cron, though not via * * * * * nor task scheduling, which isn't as much of an issue though as their dogshit docker compose: https://invoice-ninja.readthedocs.io/...