Create a new Work Object and see the Time associated to the DateTime property it would be the GMT time and the time you would enter in UI would be as per you Operator Profile TimeZone. Please have a look at difference.
Now if you run the Report Definition to show the above exposed DateTime property it should match to the TimeZone of your Operator Profile
Calling "UpdateLocaleSettings" in one of your activity will help in resolving this issue. In this activity you can pass your required timezone as a parameter and report will use this timezone. Let me know if you need any details.