In a recent change, Mexico no longer observes daylight saving time as explained here. In Sentry if you have selected Mexico City selected from the account settings, all events are time stamped 1 hour ahead of the current Mexico time.
Due to DST changes, the Symphony Desktop Application (SDA) will display the incorrect timestamp for users in Mexico for versions less than 23.4. This can be resolved by downloading the latest SDA here which contains a fix for this issue.