The Calendar may show an hour difference from what you schedule in two scenarios:
You have staff in a different time zone scheduling your work
You have a tech in a different time zone, this usually occurs when your office is near the boarder of two time zones.
Each user and tech should have their time zone setting based on their location, not the office location. Manage users and techs time zones in Users & Routes.
Manage your company time zone in Settings/Company Information.