Same on Unreal 5.5.1 here.
It worked for a time and then stopped working. I’ve been trying to go back into the space where it worked. Not sure if this is about the command line I am using because “-set:BuiltDirectory=” seems unstable: one time it works one time it doesn’t without any change to the command line.
This takes me forver because I need 4+ hours to run it somehow.