Double set of North America maps.

I just updated my Nuvi 2557 LMT for the latest maps. Update went smoothly, but when I examined the files on the unit I found TWO files under 'Internal Storage' labeled "City Navigator North America NT 2025.1 v28.10".

Is this normal? I'm at 94% full on the device and it would be nice, for breathing room, to perhaps free up some space if the double maps are not necessary.

Thanks,

jrds