I was hoping this would be the case as well, but it seems that only the first episode is available. I've seen Adult Swim do this before with Rick and Morty if I'm remembering correctly, so it seems it's pretty common when new seasons are shown from what I can tell.
I'm hoping at some point it will unlock, but unfortunately I don't have a solution myself besides getting a cable subscription for a month or two. But at that point I'd rather buy a blu-ray release of both the English and Japanese VO, even if they're separate purchases.