Hi, I had the same problem and it took me quite some time to rebuild the initramfs with the older udev version. But I managed to do this from within the initramfs console.
What made me wonder, when I did this, is the fact that the root device, which was set as UUID in grub, was not listed in /dev/disk/by-uuid in the initramfs. Is it possible that udev 240 doesn't create the uuids for cryptsetup devices? Or that the check for the root device runs, before the encrypted device is unlocked? The latter would explain why I ran into this problem. Best regards Matthias