It's pre-loaded and there's a little countdown clock for activation. Come onnn stupid clock.
I am a bit ashamed to admit that after announcing it was up for early pre-load, it took me 36 hours to find the download [emoji52]... Turns out you have to go via the game library, not the PS Store
. But not to worry, the rather large download (90gb lol) finished over night and it's now ready to go at midnight.