From the programmed Attendant Station (station 10 by default), do the following:
1. Press the Speed button.
2. Dial the asterisk (*).
3. Dial 50 on the keypad. (The display will read "System Speed Bin 50")
4. Dial year, month, day (in double digits) and hours and minutes in military time (2400 hours).
5. Press hold. Confirmation tone will be heard and Display will update to the idle position with the correct time and date.
6. Press the on/off button to turn the set off.