Jamaica is in the Eastern Standard Time Zone (EST). Jamaica observes Eastern Standard Time all year. There are no Daylight Saving Time clock changes. Some confusion occurs when the US moves to Eastern Daylight Time (EDT) in March. Which means that from March until November the US is on EDT and Jamaica is on EST, and they are an hour apart.
What does that mean for the Feast? If you are in Jamaica receiving email updates about service times, they are the same as local time. For example, if the email says services start at 10:00, that is 10:00 local time (which you should have changed your PCs, Phones and Watches to, when you landed).
If you are not in Jamaica, it is easier to think of service times as corresponding to the US Central Daylight Time Zone (CDT) which means a 10:00 AM service start time would be 11:00 AM in EDT, 10:00 AM in CDT, 9:00 AM MDT, and finally 8:00 AM in PDT.
Please let me know if you have any questions.