I have all of the Collector Editions, which prior to the last expansion, you went to the gaming retailer of your choice and preordered them. Starting with Dragonflight they now have to be ordered right from Blizzard. And if the experience that I had with the last one is any indication of what it’s going to be like with the War Within, I didn’t receive DF until two days AFTER the game went live. 
I have the Epic Edition and followed the instructions to play the Beta, but it’s not showing up on my drop down menu as an option to play. Is there a problem with the roll out?
You may have to delete/uninstall your Battle.net client, then download it back after. Seems like some clients arn’t updating, even if it says that it’s up to date.