Many CT gun owners sent their registrations in late, or they arrived late.
CT sent that letter to those people only.
CT is telling them they have to get rid of the guns/mags because CT is disallowing the late registrations.
CT probably assumes the guns were bought late and people tried to register them anyway.
These people were idiots,imo.
By applying late, they reported their weapons/mags to the state after the deadline.
Now they are stuck.
CT knows about their weapons/mags now, and CT won’t grandfather their weapons/mags.