You can set your Hours of Operation via User Hours and Time Zone via Regional Settings.
User Hours
1. Log in to your RingCentral Online Account.
2. Click Settings > User Details > Settings and Permissions.
3. Click Edit under User Hours
4. Set User Hours to any of the two options.
• 24 hours/ 7 days a week - Select if you want incoming calls handled the same way all the time, every day.
• Specify hours - Select if you want incoming calls handled differently when your business is open and when it's closed.
5. Click Save.
Regional Settings (Time Zone)
1. Log in to your RingCentral Online Account.
2. Click Settings > User Details > Settings and Permissions.
3. Click Edit under Regional Settings.
4. Set your preferred Time Zone and Time Format.
5. Click Save*.
Note: Your phone will reboot once you save.