The timezone a customer sees is determined by where the customer's web browser thinks it is. For instance, if your browser thinks you're in PST, it will show class times in PST.
At the top of a schedule, you might see Los Angeles (PST). If it's Mountain Time you need, your customers can adjust the time zone to Denver using the dropdown menu at the top of the schedule.
Customers will have a choice between where their browser thinks they are and where your classes are scheduled to take place.
Why doesn't Momence just display all classes in a studio's local time zone?
The reason for this is that many studios offer online classes. One benefit of online classes is that customers can attend class from far-away time zones.
These customers need to see your classes' start times listed in their local time zone so as not to miss class.
What if my customer is in my timezone but still sees my classes in another time zone by default?
If a simple refresh of their page doesn't fix the issue, then quitting and restarting their browser should help. They can also try clearing their browser's cache.