May be a bug for people using the potions or may simply be a bug for my friend, no idea since I don't see any other accounts of it on here. But it seems that after purchasing a jump potion for my friend so she could play Stormblood she revisited the Heavensward areas.

Aether current logs are filled and everything was marked as done in the aether current log yet she can't fly. The optional quests which unlock currents were still present and doable, but doing them didn't help anything. Every zone including Azys Lla which is only MSQ related for flying, which is all DONE because of the potion, she still can't fly in.

Dunno if this is an issue with other people too but definitely want to bring it up.