Dude, I'm simply not in this forum so often :-) Besides, the whole topic of this thread is not too far off of cheating, so yeah, we are (kind of) and you want to be to ;-)
To answer your question: I followed the exact steps above and it worked just fine, even on current version. Do you quit and restart the game when changing date? I did this at first and I doesn't work. The game has to be running at all times while doing this. Does that help? Since you mentioned that the double tap (step 8) doesn't work for you, I figured that this might be the issue, because the double tap function to quickly change between the game you are currently running and the last point in the menu you visited is actually a feature of the ps4 itself that has nothing to do with the glitch specifically.
Guess you just have to play it for hours on end in order to reach 3600 so quickly. I can't tell really, as I played this game legit for around 2 years. But I wanted to be done with it before the PS5 comes out, so I settled for just finishing it this way. Got to zone 3000ish legitimately. But yeah, it takes a lot of time and it doesn't really change. There are some "milestones" so to say that will boost you're progress by a couple of dozens or even hundreds of levels occasionally though