Brian Gaff wrote on 11/11/2016 :
But unless they change their number you zapped him for next time. In fact the
hash idea only stops pre recorded calls, humans can use hash or if this is
switched off, not press it, it matters not.

Well the vaste majority of such callers do use pre-recerded now.

The ones that can get through
seem to be the ones that change their number all the time, but at present
these are very very rare, as time is money to these people and for them
simply moving on is easier than going through to you via say name, as they
will obviously know what you will do when they start their pitch.

They don't change actual numbers, they change the spoofed number, the
number presented as caller ID - which takes them seconds to do.

That is where the system relies on the human factor.
My big issue is this.
I'm not getting calls I should because organisations like NHS will just put
the phone down not realising its just screening the call, and they often
display no number either as its through a switchboard. They hence seem to
give up.
Brian

Which is where giving such organisations a mobile number, as an
alternative, works.