General Chat has delegated weekend communications duties to Private Peon.
You can reach Pvt. Peon at 800-977-8943, follow the instructions for the extension, then listen to the voicemail for the emergency phone number.
Or just leave a message at the voicemail without bothering Pvt. Peon at home.
Or, since you don't really get gigged for a late report until after your third late notice, you can call the main number above any time tomorrow morning and speak to one of the regular office folk to explain the situation. Just ignore the first late notice you get this evening.