I got a Sport BT subscription and use VyprVPN from Sweden in my iPhone.
I can download the app from the UK appstore and login. But when I try to look at a channel I get "Turn on the location setting for the app" I have the location on for the app. Is there any other location control the app is doing? Any person that use BT Sport outside UK? Need help :-)
The irony of the BT sport app is that the pixel quality is worse than iptv that I have found and you are not a legal user of BT sport if you have to break the terms of use. So as your asking this on an iptv subreddit my advice would be to pick up an iptv sub and watch it that way