Did you find any solution? I have the same problem (boot loop, same warning message). It occured on the 4th of April this year. On this day, my DSL connection was not available for at least 6 hours. Maybe you had similar issues? I read that it might be caused by a interrupted updated.
Sadly no. I assume the SSD is corrupted, it is now stored in a drawer in case it can be restored some day but I kinda gave up on the whole smart home thing.