I have a Benelli Nova with Cantilever Slug barrel and bird barrel and my 14yo uses an 870 20ga with same setup. We both have Bushnell holsights.

We hit the range before the start of the season to verify zeros (and ourselves), then swap barrels many times between deer and bird hunts through the winter. Because the cantilever mount is independent of the receiver (the whole idea of the cantilever mount), swapping barrels has never caused a change for us.

Our guns still had the bird barrels on from last year and I put the Slug barrels on and we went to the range last week. I punched the 10 out of the center at 50 yds. My son's first shot was in the 10 ring.

In the immortal words of Ronald Reagan..."Trust, but verify"