Why is The Secret of Skinwalker Ranch season 6 not broadcast on subscribed History

From the History Webside: https://www.history.ca/

 

If you click on the show it takes you to SlackTV's website: https://www.stacktv.ca/

 

Listed on the StackTV website it says that you can't watch those shows outside of StackTV.

 

As the rights holders, they would be the best place to get answers as we simply follow their guidelines