When and till what time are phone calls welcome?

Calls to our office phones are welcome from 10.00am to 7.00pm which is our ordinary operation schedule. There is normally a minimum of 1 staff in the office during office hrs, but since we are a service company in case of emergency there might be nobody in the office even during office hrs, in such cases feel free to contact the mobile emergency number. The mobile emergency number is on 24 Hrs a day 7 days a week, but we don’t have personnel on night shifts, therefore we appreciate if you could postpone a non-urgent call to regular hours.