Well I know the alerts used to come 15 and 5 minutes before a meal and then 5 and 10 minutes after the end of a shift. This gives you 5 minutes to go clock out each time because meals need to be clocked out before the 6th (or 5th) hour and you're allowed to clock out for the day up to 15 minutes before or after the end of your shift without it showing up on a report.
But ever since we got rid of LPDAs and switched to myDevices, alerts have been hit and miss, whether it's meals, working past schedule, an alert for a GSTL to come to a lane, REDcard alerts, change requests... everything. And that was 3 or 4 years ago lol. I've seen the second alert for working past schedule come about 1 minute after the first alert, even though they should be 5 minutes apart.