Such a slow process with g translate, should try and break up the PDF and upload sections. So I think it Looks like there are 2 different high speed continuous shooting modes. The “+” mode does 12 FPS but only some EF lenses are supported (so bad news for third party I am guessing?). Otherwise, the other mode does 6 FPS (fully mechanical) and 8fps (electronic first curtain).
The 12 FPS also come with a bunch of conditions/ factors, like battery level (over 60%), temp, over 1/1000th sec and more.
The Eos R manual came out for all to see basically when it was announced and available for preorder. It made me a bit cautious that the same was not the case for the RF.