I can do a S1050 Dillon tool head change very quickly. Should take you no longer than 10-15 minutes
but......
Add 5 minutes if changing primer size.
but........
Add about 5 minutes if moving to a prep process for rifle if you are using the swage rod feature. I cut representative brass to help me with this
but........
Usually when I change calibers Ive made so much ammo that I want to spend a bit of time cleaning the machine so I may spend 30-45 minutes using solvent to wipe down under the shell plate, clean various orifices, remove old grease and replace with new.
Sure from pistol caliber to pistol caliber not concerning yourself with the smudge from loading 5000 rounds of the first caliber you could change in 10-15 minutes but prudence kind of suggests you do some PM while taking the machine apart and inspect parts, replace anything worn, grease/oil.