Lightroom Classic: 100 picture limit for panorama?

Hi i am doing panorama and when i am at 100 picture in would let me select the option in the menu for panorama, but not at 101[menu option grayed]. Is there any reason for that? i saw no reference for that limit anywhere... only the 65000 pixel limit which i am far from that. for example a 80 picture panorama gave me 36000x11000.

and if there is a official limit of 100 is it possible to somehow make smaller panorama and stitch them together. I have had difficulty doing that... always an error message (could not merge...)