I’m doing a similar project, printing an entire roll as a single image, but mine will be viewed from about a foot away, winding along the walls of an exhibit, so I’m going to use topaz to upscale it. Luckily the original images are 35 mm slides comped together into a panorama, so there will be film grain on display and that’s perfectly fine for the context. But while I can have as much big soft bubbly round film grain as I want, jagged pixels and digital compression artifacts are unacceptable.
I think the practical limitation is actually going to be how big of a file is being sent to the printer & how far it gets before it crashes, eating rolls of fine art paper. A 300 dpi uncompressed file 24 feet long is almost certainly greater than the printers buffer will handle, even on this big large format printer.