@Nullable
	public static Integer readTimeZone(@NonNull final Data data, final int offset) {
		if (data.size() < offset + 1)
			return null;

		return data.getIntValue(Data.FORMAT_SINT8, offset);
	}
Offset from UTC in number of 15 minutes increments. A value of -128 means that the time zone
offset is not known. The offset defined in this characteristic is constant, regardless
whether daylight savings is in effect.

@param data   data received.
@param offset offset from which the time zone is to be read.
@return the time offset in 15 minutes increments, or null if offset is outside ot range.
ble-common/src/main/java/no/nordicsemi/android/ble/common/callback/TimeZoneDataCallback.java