Got it working as expected! As always, thanks Javier!
Yes this is also there in the 188.8.131.52.
In addition, you can zip the files and they will be submitted as a job group which can be joined into a single PDF. The files will be joined in alphabetical order.
I guess this also goes without saying but the Submit Job interface will also create a job group when multiple files are uploaded and submitted as a single job.
Is this the same in 184.108.40.206?
WIth that version of FFCore you need to submit the job as either a Manifest in which multiple rows are part of the same job or via JMF adding multiple files to the RunList.