Each Alexa device uses timers and alarms independent of other Alexa devices registered on your Amazon account. Use your voice to set up or cancel a timer or alarm, and you can then manage them in the Alexa app. You can set a single timer or alarm up to 24 hours ahead.
If your device is muted, or not connected to Wi-Fi, your timers or alarms still go off.
The Alexa app can manage up to 100 timers and alarms.
Do Not Disturb setting on the Alexa app doesn't block timers and alarms.