Combination of offsetHour:offsetMinute is limited to the range -12:59 to +13:00.
This is the Universal Coordinated Time hour and minute offset (offset to seconds is always 0) that can be applied to an instance of Time. The application of this offset to the Time hour and minute attribute values provides Greenwich Mean Time. A 26 hour total interval is provided to account for the application of a 'Daylight Savings' component to some time zones.
Use of the utcOffset references the time specified by timeType to Greenwich Mean Time thereby inferring Time Zone. When the utcOffset is defaulted or equivalent to 0 then:
timeType equal to 'utc' provides actual Greenwich Mean Time.
timeType equal to 'gps' provides 24 hour clock GPS time at the Greenwich Meridian.
timeType not specified provides unreferenced 24 hour clock time.