Unable to dualboot « device is not formatted »

[2quignot]

Hello I have install Divisé for Dualboot
iPad AIR 1 (4,1) on iOS 12.5.7 to 10.3.3
The installation process sign everything but when I want to dualboot with Ramiel i have a boot loop in verbose and need to reboot to main OS

I have this message in loop

apfs_mount : 14568: unsupported apfs_incompat ible_features (8) : unable to nount
apfs_vfsop_mount: 622: failed to mount devvp (/dev/diskOs1s4): 75
liskDs1s4: media is not formatted.

Thank you for your help