Silencing unknown callers

The feature for silencing unknown callers is great BUT I have a problem...

My landline home phone is an unlisted number so when someone calls me from our landline phone, my iphone is also being silenced.

I doubt there is any way to override this and allow my iphone to announce these calls. I fear my family won't know to dial *82 to unblock our landline...

So the feature is great in all ways but for our unlisted landline. I can only hope someone has a trick to help me out!

tks!