The current GMT offset for the Europe/Budapest timezone is GMT+2, because the Daylight Saving Time started at Sunday, 30 March 2014, and the clocks were advanced by one hour (see http://www.timeanddate.com/worldclock/city.html?n=50).
You can verify that with
BOOL isDst = [currentDateTimeZone isDaylightSavingTime];
// --> YES
NSTimeInterval dstOffset = [currentDateTimeZone daylightSavingTimeOffset];
// --> 3600
If necessary, you can compute
[currentDateTimeZone secondsFromGMT] - [currentDateTimeZone daylightSavingTimeOffset]
to get the "default" GMT offset for your timezone.