What annoys me is the BT refuse to add the *International* flag to the anonymous call blocking service. I had the anon call block on my elderly fathers line after I discovered that he was becoming very "suggestible" to the call centre scam scum.
The Anonymous flag block was very effective, however the overseas scum could still reach him. I looked at phones with spam blocking built in but to introduce him to a new phone with a new menu system was a step he wasn't able to take at that late point in his life, where illness had all but killed his ability to take in new information and retain it.
It is unacceptable for BT to hide behind excuses. They know whats going on, they *can* do something to reduce it, but seemingly refuse to. Its one of the reasons that I have nothing with any BT group retail arm.
My mobile has Truecaller installed - as my mobile is my primary phone for for work and I get all sorts of one off calls from people not in my contacts so I find Truecaller flashing the screen red for a spammer useful to flag up the parasitic scum that interrupt our days.