Web alarm clock for 12:20 a.m.
You are getting ready early to relieve the guard at the residential village gate, so set the alarm for 12:20 am while there is still time to check your things. That leaves a calm buffer before 1:00 am for putting on your uniform, collecting the logbook, and reaching the gate without rushing through the quiet streets.
Before leaving for the gate, play a test sound and notice where it comes from. Your phone may quietly send the alarm to earphones left in a bag or connected by Bluetooth, making it easy to miss while you prepare in another room. Select the intended speaker, raise the volume to a useful level, and keep this page active. If the browser is closed or the phone falls asleep, the alarm may not sound, which could leave the next guard waiting at the gate.
A late-night handover is easier when food and drink do not add another task just before departure. Have a light snack and some water earlier, then pack a covered drink if the guard post allows it. Leave a heavy meal for after the shift change, when you are no longer watching the minutes or travelling at night. By 12:20 am, you can focus on the handover notes and arrive ready to take over.