@sven @Lakotaubp Whoops, I thought I'd searched for some keywords before I posted this. Sorry about that. I got it working by booting into TWRP and wiping the cache and data partitions. Works fine now!

I'm having trouble installing Ubuntu Touch on my oneplus 6

Most of the install works fine, It gets stuck at Preparing Recovery. Any help would be greatly appreciated.

Full Error Message -

"Error: adb:preparesystemimage: Error: {"error":{"code":1,"cmd:"adb -P 5037 mkdir -p /cache/recovery"}, "stderr": "mkdir: ''/cache/recovery":Required Key not Available"

Thanks in Advance.

George