Bug with NSDateComponents (execute this method in simulator and in physical device to see different results)

device.txt

😡 2000 --> 1999-01
😏 2001 --> 2001-01
😏 2002 --> 2002-01
😏 2003 --> 2003-01
😏 2004 --> 2004-01
😡 2005 --> 2004-01
😡 2006 --> 2005-01
😏 2007 --> 2007-01
😏 2008 --> 2008-01
😏 2009 --> 2009-01
😡 2010 --> 2009-01
😡 2011 --> 2010-01
😡 2012 --> 2011-01
😏 2013 --> 2013-01
😏 2014 --> 2014-01
😏 2015 --> 2015-01
😡 2016 --> 2015-01
😡 2017 --> 2016-01
😏 2018 --> 2018-01
😏 2019 --> 2019-01
😏 2020 --> 2020-01
😡 2021 --> 2020-01
😡 2022 --> 2021-01
😡 2023 --> 2022-01
😏 2024 --> 2024-01
😏 2025 --> 2025-01
😏 2026 --> 2026-01
😡 2027 --> 2026-01
😡 2028 --> 2027-01
😏 2029 --> 2029-01
😏 2030 --> 2030-01
😏 2031 --> 2031-01
😏 2032 --> 2032-01
😡 2033 --> 2032-01
😡 2034 --> 2033-01
😏 2035 --> 2035-01
😏 2036 --> 2036-01
😏 2037 --> 2037-01
😡 2038 --> 2037-01
😡 2039 --> 2038-01
😡 2040 --> 2039-01
😏 2041 --> 2041-01
😏 2042 --> 2042-01
😏 2043 --> 2043-01
😡 2044 --> 2043-01
😡 2045 --> 2044-01
😏 2046 --> 2046-01
😏 2047 --> 2047-01
😏 2048 --> 2048-01
😡 2049 --> 2048-01

printDate.m

- (void)printDate {
    NSCalendar *calendar = [NSCalendar currentCalendar];
    
    NSDateFormatter *f2 = [NSDateFormatter new];
    f2.dateFormat = @"YYYY-MM";
    
    for (int i = 2000; i < 2050; i++) {
        NSDateComponents *monthComp = [NSDateComponents new];
        monthComp.year = i;
        monthComp.month = 1;
        
        NSDate *dateMonth = [calendar dateFromComponents:monthComp];
        NSString *generated = [f2 stringFromDate:dateMonth];
        NSString *expected = [NSString stringWithFormat:@"%d-01", i];
        NSString *icon = [generated isEqualToString:expected] ? @"😏" : @"😡";
        NSLog(@"%@ %d --> %@", icon, i, generated);
    }
}

printDate.swift

func printDate() {
        let calendar = NSCalendar.currentCalendar()
        
        let f2 = NSDateFormatter()
        f2.dateFormat = "YYYY-MM"
        
        for i in 2000...2050 {
            let comp = NSDateComponents()
            comp.year = i
            comp.month = 1
            
            let date = calendar.dateFromComponents(comp)!
            
            let gen = f2.stringFromDate(date)
            let exp = "\(i)-01"
            let icon = (gen == exp) ? "😏" : "😡"
            
            print("\(icon) \(i) -> \(gen)")
        }
    }

simulator.txt

😏 2000 --> 2000-01
😏 2001 --> 2001-01
😏 2002 --> 2002-01
😏 2003 --> 2003-01
😏 2004 --> 2004-01
😏 2005 --> 2005-01
😏 2006 --> 2006-01
😏 2007 --> 2007-01
😏 2008 --> 2008-01
😏 2009 --> 2009-01
😏 2010 --> 2010-01
😏 2011 --> 2011-01
😏 2012 --> 2012-01
😏 2013 --> 2013-01
😏 2014 --> 2014-01
😏 2015 --> 2015-01
😏 2016 --> 2016-01
😏 2017 --> 2017-01
😏 2018 --> 2018-01
😏 2019 --> 2019-01
😏 2020 --> 2020-01
😏 2021 --> 2021-01
😏 2022 --> 2022-01
😏 2023 --> 2023-01
😏 2024 --> 2024-01
😏 2025 --> 2025-01
😏 2026 --> 2026-01
😏 2027 --> 2027-01
😏 2028 --> 2028-01
😏 2029 --> 2029-01
😏 2030 --> 2030-01
😏 2031 --> 2031-01
😏 2032 --> 2032-01
😏 2033 --> 2033-01
😏 2034 --> 2034-01
😏 2035 --> 2035-01
😏 2036 --> 2036-01
😏 2037 --> 2037-01
😏 2038 --> 2038-01
😏 2039 --> 2039-01
😏 2040 --> 2040-01
😏 2041 --> 2041-01
😏 2042 --> 2042-01
😏 2043 --> 2043-01
😏 2044 --> 2044-01
😏 2045 --> 2045-01
😏 2046 --> 2046-01
😏 2047 --> 2047-01
😏 2048 --> 2048-01
😏 2049 --> 2049-01