Did you ever have BIOS 3.16 installed?
I think I did but I am not sure. However, every time I got a notification about a new BIOS update availability, I installed it. So I must have installed 3.16?
Could you use the UEFI Shell Method to downgrade to the 3.16 release, then use the same UEFI shell method again with the 3.18 release to lock in the new Secure Boot keys?
I’ll have a look at this. Thank you!