There's a misleading/incoherence usability issue, with the Crown Store vs ESO Plus accounts. I wanted to play Greymoore. Since I also have an ESO Plus account, I thought that maybe I can access it now... But the issue here isn't about some delay between buying the DLC and having access via an ESO Plus account.
I have ESO+ and tried to start Greymoor via a wayshrine, but the game says that it's locked and that I must upgrade. So i click "upgrade", then it takes me to the crown store to purchase it, HOWEVER the UI tells me that its ALREADY purchased and the button to purchase it is grayed out (I can't click it to buy the DLC). On one hand it says that I don't have it that I must upgrade, but on the other hand it says that I've already purchased it: there's no clue whatsoever suggesting that having an ESO Plus account, there's a delay before accessing the DLC and I must buy it from the Web Site if I want to play it now. In this regard the Crown Store's message is misleading/incorrect/incoherent.