Ah, this makes sense. I deal with some data analysis that has times referenced to the GPS epoch, but also includes all the leap seconds added from the GPS epoch

Ah, this makes sense. I deal with some data analysis that has times referenced to the GPS epoch, but also includes all the leap seconds added from the GPS epoch through September 19, 2013. So I've spent a fair amount of time dealing with this but haven't had to get as deep as you have. thanks for the detailed reply