replaceWithSequence

Hi, I've noticed recent behavior with the function:
newFootageItem = "path/image.1001.jpg";
footageItem.replaceWithSequence(File(newFootageItem), true);

When it runs, it's not replacing the footage with a sequence. I'm only getting the first image of the sequence.  I believe this used to work correctly, but I've been heavily editing this script. I might have changed something I shouldn't have, but running previous versions of the script from months ago yield the same result. 

Thanks for any help.