2011 GT Auto Trans sluggish at times

I have about 3000 miles on my GT now and ever since I have had it the transmission has seemed quirky when it's cold. Very slow to go into gear if its been a few days since driving it. Almost like the old automatics when the filter was dirty or low on fluid. When you put it in gear and press on the accelerator, it very slowly moves itself forward or backwards for several feet for about 15-20 secs. Once it warms up it's fine. I've been putting off making a service appt thinking maybe after it breaks in it will get better but it's starting to worry me. Anyone else having this problem with the auto 6 speed? I live in NYC so I don't drive it but every now and then and getting a service appt can be a pain.

Well I can definitely say its not my driving style. Like I said in my email to you, my car is now in NYC, parked in the garage of my apt building, and I take it out maybe once every 2 months and every time it still does this same thing - takes 15-30 seconds to actually go fully into gear when you first move it out of park after it has sat for more than a few hours. The car has 3600 miles on it - half of them came from driving it here from Arkansas - and since I rarely drive it I never think about it except when I do get in, and then its always a Saturday or Sunday and by Monday I have forgotten about it again. Plus I won't drive it when the streets are wet, when its raining, icy, misty, cloudy, etc lol and up here this winter that has limited my driving opportunities. It sits in the garage under a car cover like brand new - never been driven in the rain a single time yet. When it warms up and dries outside I'll take it in.