Use Alerts for instance:
"New alert" in ActionBar.
It will notify you via popup on specific time - when you'll have browser opened.
If not then you'll get an email, but you have to setup cron for that! http://www.epesi.org/Cron
Also make sure that you've set an email etc in Menu -> My Settings -> Control Panel -> Alerts. Every user sets in on his own.
Other great feature of EPESI is watchdog (that green eye) - make sure you've got an applet on the dashboard - it's a way to observe changes that are important to you.
There is also agenda applet, where you can show all upcoming events.
However there is no reminder for specific state of the record. So all my suggestions are not exactly what you need, but I believe you'll find something suitable for your needs.
Regards,
Adam
