Interesting, you are correct. It seems all our job tickets are that way. We use FF Print Manager and when a job ticket is saved it is a "save and associate" action that creates the job ticket. I guess FFCore doesn't have the same logic as FFPM? We don't have this issue submitting through FFPM.
I am using 6.1.2 and I am not seeing the issue you describe. I am suspicious that the xpf you are using has jobname set to "default name". For example within the xpf is the line:
<job-name syntax="name" xml:space="preserve">default name</job-name>
On Core 6.1 when using the submit job dialog, anytime a job ticket (.xpf) is associated / uploaded with file the job name drops and it shows up as "default name" for a job name in core or at the printer. This even occurs if you override the job name and type something in for file name in the dialog. Is this a bug?