In our exploration of the Patch 11.0.7 PTR, we've made a terrible discovery… the High Winds debuff prevents all flying on the Siren Isle!
The High Winds debuff prevents flying on the Siren Isle.
Currently, you cannot fly whatsoever on the Isle, though what's not entirely clear is whether this is a permanent restriction, or something that players are intended to overcome in some way over the course of the patch. We've also found several other spells in our database relating to the winds, and although it's unclear exactly how they'll be used, they do hint at the possibility that there may be a way to overcome the restriction.
Then again, it is worth noting that the island is fairly small, roughly the size of other Battle for Azeroth island expeditions, so it may be entirely intended that we not zip across it too easily.
Therefore, it's also very possible that these spells are used for some kind of world quest or other event, with a common name and icon referring to the same winds that keep our mount from flying.
Convenient grapnel hooks will help navigate the isle's tall bluffs.
Verticality is still present on the isle though, as convenient grapnel hooks are located all over the places to help navigate the tall peaks and shoreline valleys. There's also quite a bit of water throughout the island, so bring your Anglers' Water Striders!