When is a check due, and what happens if it is forgotten?

The next due date is worked out for you: date of the last valid check + the thermometer's frequency (30 days by default). A new thermometer counts from the day it was added. The tile shows "due on" with the date.

1. On that day the tile switches to "To check" and a task shows up in Today's tasks, like a walk-in temperature.
2. If it is missed, the tile shows "overdue since" and the task stays overdue until it is done; a late check resets the clock from its own date.
3. The manager can also settle a miss without hiding it: in Today's tasks, "Clear overdue tasks", giving the reason ("Establishment closed", "Done, but not logged"). The reason is written in the log and the due date starts over from there.

No need to wait for the due date: after a drop, a trip through the dish pit or a doubt about a reading, check the thermometer right away; the check joins the log and pushes the next date back accordingly. The full history is in "History" and in Inspection mode, with "Export PDF" or "Send" for the period you choose: that is the calibration log the health inspector asks for, without the binder.

Tip: a check that is two periods late does not create two tasks a day, but one per missed due date: clear them all at once, the log keeps one line per period.