Ok, been driving me nuts but think I finally figured out what to do with the front three.
When the HP came out I remember asking about the differences with the v3. I reVP180v3 for a M80v4 non HP.
I listen to music in 2ch and movies in full 7.2 so really there is no need for the centre channel in a HP.

My Anthem can be setup for 2 ch in music and 7.2.x with movies so this should work fine.

Anthem AVM30
Anthem MCA50