My DirecTv local stations would dissappear when I got beyond my ZIP CODE. This is normal... I suspect some areas are larger than others. Years past we could see our local stations anywhere we were at. This changed about five years ago I think it was... 40 miles outside your local assigned address does sound like a bit far to still get your local stations.
If was going to be outside my original assigned zipcode location I could call them and temporary change my local address. I think they only would do this for just a couple of times over the year.
Seems like I hear DISH NETWORK has no problem in doing this change anytime you wish...
If this is going to be your new permanent address then I would put in a change order.
Roy Ken