I was similarly disappointed but IIRC it was delayed to September 6th.
I wonder how will it run in Act 3 since DX11 is so much more performant than Vulkan and I assume they use either MoltenVK or straight Metal. It’s likely the reason for the delay.
I just checked Wikipedia which I think I got it from and it states 9/6 but the link cited as source doesn’t state it anywhere.
grumble