Evening ladies and gentlemen! Just in case you didn't know, Sony has released the Oreo firmware on their website. It has to be installed via usb for now. I just did it to my Sony 900e and installation was a breeze.
Edit: download link https://www.sony.com/electronics/support/lcd-tvs-android-xe90xx_x90xxe-series/xbr-75x900e/downloads/00015669
Link?