Not sure why I can't go to v10 as it says on the wii.guide cios. I downloaded it from that site too. : r/WiiHacks
GitHub - davebaol/d2x-cios: A custom IOS for the Wii and Wii-U console, i.e. an IOS modified to add some new features not available in the official IOS.
how to install wii flow 3.0 with cios d2x ios 249 and ios 250h - YouTube