Seems to me the dash in the disk uid gets converted to "xtd", thats why the partition can't be found?

After 4.12-9.14 the workaround of choosing the previous kernel version no longer works. After pressing enter once you can still enter the encryption password and continue starting up. Is there any news on this?

Same here. After the latest update to 4.12-8.13 I have the same issue. If I choose 4.12-7.11 to boot from the problem does not occur. I'm asked for the crypt password without error message. If I choose the default 4.12-8.13 option the problem occurs again.