The limit isn't with people logging into the app - it's the limit on the number of devices that can play live content at the same time. You can have as many devices as you like watching replays and VOD clips.
And on that note, we've temporarily increased it to 3 whilst we investigate potential issues in some clients with not freeing sessions. Standard behaviour is 2 concurrent live streams though, and I'd expect us to return to that in January.