Thanks Nicci!
I am still unclear on the 2-4-1 issue though. I understand that if I use my 2-4-1 on my HHA, any of my friends and family can be the companion...
BUT
on my HHA, if one of my new friends and family has a 2-4-1, can we use their voucher under my HHA. Essentially their 2-4-1 but "my" avios.