There is hope, but since Apple has their own plans for an OTT service that would compete with SlingTV, that hope is anorexic at best.
Using AirPlay mirroring to your AppleTV may also be a low priority since Apple may not approve that change to the SlingTV app on iOS.
If you have a Macintosh from the last year or two you should be able to go to the SlingTV website and AirPlay from your Mac to your AppleTV.