You arrive in another city and a meeting that used to say 10:00 now says 11:00. That alone does not mean the organizer moved it. A timed event can represent the same moment while the calendar shows a different local time.
Check the display before editing the invitation
In Google Calendar on a computer, open Settings and look at the primary time zone. You can also display a secondary zone: useful when your calendar needs to show both home and destination time. These instructions concern events with a start time, rather than all-day entries.
Next, compare the invitation's date, event time zone and duration with the organizer's message. If you open the editing screen to inspect a setting, leave without saving unless you intend to change the appointment. Dragging the meeting to its old position can reschedule it instead of fixing the display.
Try the conversion on a separate event
Create a private practice appointment with no guests, choose an explicit time zone, then view it in the two zones. Use the date of your actual trip. This lets you check the display without sending updates to anyone.
For a recurring meeting, inspect dates around clock changes too. The difference between two cities need not stay constant all year. Google also warns that changes to regional time-zone rules can affect previously created events. When confirming a meeting, include a date and a city or named zone; “tomorrow at ten” leaves too much unstated.