Amazon has opened pre-orders for the Fire HD 8 Covers. The styles include Charcoal Black, Mickey No Bad Days, Mickey Through Time, Parrot, Plum, Sandstone White, Turtle and Twilight Blue. If you are interested, you can pre-order any of the covers with the following link from the online retailer:
The covers feature a built-in stand, magnetic connection and microfiber interior. It also supports wireless charging for 10th Gen Fire HD 8 Plus tablets. According to the product pages, the covers will be coming out on June 3, 2020, on Amazon in the U.S. region. The new tablets are also coming out on the same day.
You can find out more details on the Fire HD 8, and how it compares against similar tablets, with this guide.