NSString *formatStringForHours = [NSDateFormatter dateFormatFromTemplate:@"j" options:0 locale:[NSLocale currentLocale]];
            NSRange containsH = [formatStringForHours rangeOfString:@"H"];
            BOOL shouldUse24HrTime = containsH.location != NSNotFound;
            format = (shouldUse24HrTime) ? @"H:mm" : @"h:mm";

Now, on Catalina, I am realizing that this code is failing.  Unfortunately, I don't know when this started to fail. 

It always returns 'h a', whereas previously it returned 'H'.

Is anyone else seeing the same thing?  If others can confirm this same apparently errant behaviour I'll file a bug report.  First, I want to be sure it's not just my system…

Also, does anyone know an alternative, or better, way to determine the time format of the system? ('Use 24-hour clock' as found in Date & Time System Preferences)

Thanks,

Sandor