Changing 2 W tickets in a group of 7

Hello all,
Before I try ringing Virgin about this, may I ask you experienced travellers a question about changing W tickets, which is a bit new to me.
I have 1 booking with 7 people on it, to go LGW-MCO. I managed to get flexible W tickets at the time in case I needed to make changes, and I now have 2 of my party considering visiting relatives up in New England at the end of the trip, which leads me to 2 questions:
1) Despite the fact I have one booking, can I split out and change the return date for two of my party, and would it cost extra for a W ? (they could then get a internal return ticket up MCO-BOS)
2) As they want to visit up near BOS / JFK area, could I simply change their return airport, without affecting the rest of my party returning from MCO. Again, any fee or gotcha's? (I realise this would probably bring them to LHR nor LGW)
Many thanks for advice (or other bright ideas!) in advance
Before I try ringing Virgin about this, may I ask you experienced travellers a question about changing W tickets, which is a bit new to me.
I have 1 booking with 7 people on it, to go LGW-MCO. I managed to get flexible W tickets at the time in case I needed to make changes, and I now have 2 of my party considering visiting relatives up in New England at the end of the trip, which leads me to 2 questions:
1) Despite the fact I have one booking, can I split out and change the return date for two of my party, and would it cost extra for a W ? (they could then get a internal return ticket up MCO-BOS)
2) As they want to visit up near BOS / JFK area, could I simply change their return airport, without affecting the rest of my party returning from MCO. Again, any fee or gotcha's? (I realise this would probably bring them to LHR nor LGW)
Many thanks for advice (or other bright ideas!) in advance