I do not think the method your using is the best way to solve what your wanting. Let me look at a few things and I might suggest something. Ideally you should keep it on a single ticket but when you print bills it automatically prints separate tickets for entities. I am thinking a state flow for order grouping and we store an entity to each group then a command to auto split the ticket and print based on that entity and order group. I think this might be possible it may take me till later today to provide an example though I have a meeting in about 30 minutes and it may take half the day.
An idea of how we might split the tickets can be found here:
Its not exactly the same thing but we can use some concepts shown.