Iphone 12 & 13 cases are pigmented coated leather so they won't patina at all until you physically wear through the layer of paint they apply to them. Left on their own it usually only happens on the edges.
The old Iphone X Saddle cases weren't pigment coated.
I was hoping for a repeat with the Golden Brown case too but that clearly wasn’t going to happen.
After just digging the old X case out it was a lot flimsier than I remember it, the Andar is way nicer.
It did patina well though, IMO. After about a year of use:
Very much like mine for the iPhone 8. It was good leather.