A practice has a downtown clinic in Pacific time and a satellite office in Mountain time. Booking a 2:00 visit at either should mean 2:00 on that clinic's wall, wherever the person at the desk happens to be sitting. Goji keeps two time zones apart so that works.
The location's time zone
Each facility has a time zone of its own, set under Settings, Scheduling, Facilities. Every appointment at that facility is booked and displayed in it. Patients' appointment times in messages and reminders follow the facility too, so a reminder says the time on the clinic's clock.
The choices are the US and Canadian zones, from Newfoundland to Hawaii, including the no-daylight-saving ones for Regina and Phoenix. When you add a facility, the zone starts as your own and you can change it.
Your own time zone
Your own time zone is a separate setting, under Settings, Display, Your time zone. It is personal and not shared with the practice. It decides what Today and Yesterday mean for you and which dates the Calendar and dashboard open on.
Goji detects it from your browser. If you have a VPN or you are on a shared device, it can guess wrong, so you can pick the right zone yourself. When your choice doesn't match where your connection seems to be, a warning appears under the setting, telling you this is the first place to check if dates or the Today label look off.
In the facilities list, a facility whose zone differs from yours is marked as not matching your time zone, so you notice before you read a time as your own.