I should have said make 4 copies of the job with 4 destination printers. Each of the destination printers use a different media name (which maps to a unique tray). Each destination printer has copy count set to 4. You can choose uncollated or collated depending on you print requirements.
If you still have a timing issue with the printing you can use the Collect node (assuming you have the Output Management license) as a delaying mechanism -- see screensnap. You can set different amounts of time for the each branch before print.
You are correct the FFCore cannot submit jobs to print with a specific tray. However if the trays are loaded with media with unique names, FFCore can submit jobs to be printed with a specific media. Assuming you have the Advanced Automation license, you can use the Split node to create 3 copies of the job -- see https://forum.support.xerox.com/t5/FreeFlow-Core/One-file-multiple-outupts/td-p/227498 . Then have 3 specific print nodes on each split node branch. The print nodes will have unique printer destinations targeting the media loaded in each tray -- see screensnap. Some printers enable the display of tray associated with the media (in black background hover information) The number of copies can also be specified with the printer destination or at submit GUI.
Note: ApeosPort is not supported by FFCore.
