App Store 'Update' overwrite plist?

[IronMike]

I have seen a bunch of similar questions but I want to make sure that my exact question is answered.

I'm about to release an app that uses 4 plist files that are stored on the device like so:

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];	
NSString *filePath = [documentsDirectory stringByAppendingPathComponent:@"myFile.plist"];	
BOOL success = [fileManager fileExistsAtPath:filePath];

if (!success) {		
   NSString *path = [[NSBundle mainBundle] pathForResource:@"myFile" ofType:@"plist"];
   success = [fileManager copyItemAtPath:path toPath:filePath error:&error];
}

In the future if I make changes to the app, I do not want to overwrite these files. Users will be very mad if they lose all the settings in the files. Since the files are in the documents directory, I am guessing that the files would not be overwritten on an update. Also, when I delete the app in the simulator and reinstall, all the plist files are still in tact. I must "Reset Content and Settings..." for the plist files to be cleared out.

So am I correct that if I release an update in the future, it will retain my plist files?

[JasonR]

An update will not change any files in the documents directory.

But if the user deletes the app, the documents directory is also deleted. But they might be able to restore from an iTunes backup.