If you find that event times in the app are incorrect, the time zone may be incorrect. You can change this by selecting "Me"> "Edit Profile"> "Time Zone" in the app. Look up and choose, for example, "London".
If you log in to the app when you are abroad (in other time zone), the time zone will change automatically. Then you must change as explained above. If you are continuously logged in (which is most common and appropriate), you will only receive a notification that you are in a new time zone.