Methods for producing encased products using selectable first and second horns to thereby produce products in selectable different casing types include: (a) providing an apparatus having a first horn that, in operation, is configured to be in fluid communication with a filler pump located upstream thereof; (b) removing the first horn from the apparatus; and (c) mounting a second horn assembly comprising an intermediate pipe segment in fluid communication with a casing horn to the apparatus. The casing horn can pivot side-to-side. Related apparatus, systems, kits, assemblies and computer program products are configured to allow dual operational modes of producing encased products using first or second horns.