Cantilever scope mount VS Medium rings ?

[FatCatsDad]

What is the proper application for a cantilever, PEPR scope mount.

I was taught that the optics should be mounted as low as possible to the centerline of the bore axis.
Meaning to me the lowest rings possible.
The cantilever mount raises the scope of that note axis center more than the highest rings.

So when is the right time to use them ?

 

[Buck1950]

If you need to move the scope forward or backward more that mounts allow; if you need clearance for bolt; if you need ejection clearance; . . .