Dragon Isles will either be the location of 8.3 or the continent for 9.0. Compiling a list of hints that support this claim:
• Dragon Isles were hinted at by the
Unscarred Black Scale item from Island Expeditions.
• Each of the dragonflights were featured prominently during each of the Legion zones and other quests.
• Black Dragonflight - Ebonhorn in Highmountain.
• Blue Dragonflight - Senegos and Kalecgos in Azsuna.
• Green Dragonflight - Ysera's death in Valsharah.
• Red Dragonflight - Featured during the Death Knight class campaign.
• Bronze Dragonflight + others - The seemingly out-of-nowhere Chromie scenario added in Legion.
• The Sylverian Dreamer, a cash shop mount emerges just a few months prior to the announcement of the 8th expansion at Blizzcon 2019. There isn't a solid pattern here, but some cash shop mounts that are released close to an expansion announcement appear to be designed during the art development phase for the next expansion. See Heart of the Aspects prior to MoP.
• Just about every single creature NPC has had a model upgrade up until this point.... except DRAGONKIN.
•
Most interestingly imo - Wrathion has returned with a custom model around the time we're dealing with N'Zoth. If you buy into the
Aspect Theory the End Times dungeon released years ago was a general outline for the upcoming conflict with N'Zoth. It's possible that it's in fact a grown Wrathion impaled on the spire of Wyrmrest Temple, and he was being assisted by the newly front-and-center NPCs of Baine, Tyrande, Sylvanas and Jaina at each of the corresponding dragonshrines they were at during End Time. We know the dragon aspects were created by the Titans SPECFICALLY to counter the Hour of Twilight being brought on by the old gods. We are currently diving deeply into protective Titan technology with Magni and the Heart of Azeroth, N'Zoth is out of his prison, and it appears Wrathion may have the answer - to return to the Dragon Isles and recover whatever lost magics were used to empower the aspects. I suspect Murozond will also make an appearance during this last confrontation with N'Zoth.