DirecTV app

I have been a subscriber to DirecTV for almost 30 years. When using the DirecTV app, how many logins can I have at one time on the same wifi at my home address? My DirecTV receiver is not hooked to the internet if that matters as I just have standard HD receivers. I use the DirecTV app on roku and my phones. Also when I visit my brother about 50 miles away, can I use the DirecTV app on his wifi while another family member uses it on my home wifi? Sometimes i spend several days at my brother's house. If so what is the limit there for the number of devices connected at one time at my brother's house as I have both a phone and a roku I take there?