Fixed now - the problem was that the partitions UUID has changed as an effect of my actions so I had to update /boot/grub/grub.cfg with the new ids, which I got by running (as root):
blkid
How to fix grub after moving root partition?
Fixed now - the problem was that the partitions UUID has changed as an effect of my actions so I had to update /boot/grub/grub.cfg with the new ids, which I got by running (as root):
blkid