In message , Chris J Dixon
writes

My point is that, unless you can explain an aspect that I am
overlooking, when they get to my door, it is down to their memory
to recall that I am officially opted out.

Yes, you are correct. Problem is, they should not be getting to your
door, or even to the postie or his bag, van, whatever. The theory is
the postie delivers everything he is given. My office was small rural,
and I can see that in a much larger office, there may be breakdowns in
communication, which does not help you.
--
Graeme