Zos have managed to confuse about launch date, but according to current info this is early access until launch June 5th for all platforms not just consoles.

And

The Fang Lair and Scalecaller Motif chapters and Style Items will begin dropping from their respective dungeons shortly after the launch of Summerset.

The Fang Lair motif chapters drop from the final boss in Fang Lair; rarely on Normal, more often on Veteran, and guaranteed on Veteran Hard Mode. The Style Item, Dragon Bone, drops from all bosses in the dungeon; more often on Veteran than on Normal, always from the final boss, and more from the final boss on Veteran Hard mode.
The Scalecaller motif chapters drop from the final boss in Scalecaller Peak; rarely on Normal, more often on Veteran, and guaranteed on Veteran Hard Mode. The Style Item, Infected Flesh, drops from all bosses in the dungeon; more often on Veteran than on Normal, always from the final boss, and more from the final boss on Veteran Hard mode.