Cancelling a companion reward ticket

Can someone tell me what will happen if I cancel my Y ticket that also has a corresponding companion reward ticket (using CC voucher).
Will I just lose the tax I paid on the companion ticket (plus the voucher itself) ?
Reason I ask is that I have booked the Y and T tickets, in the hope that someone will take pity [:#] and allow us to upgrade to PE on the day.
Availability is not looking good (plus if PE is available they will turn noses up at the T ticket and ask for more cash no doubt!) so I am now wondering whether I should bite the bullet and book the trip with VH.
VA PE flights are coming in at £2500 each for our dates.[:0][:0]
VH package prices with PE upgrades and looking very reasonable in comparison and PE is available. The hotel we had booked is also available.
Thanks
L2H
Will I just lose the tax I paid on the companion ticket (plus the voucher itself) ?
Reason I ask is that I have booked the Y and T tickets, in the hope that someone will take pity [:#] and allow us to upgrade to PE on the day.
Availability is not looking good (plus if PE is available they will turn noses up at the T ticket and ask for more cash no doubt!) so I am now wondering whether I should bite the bullet and book the trip with VH.
VA PE flights are coming in at £2500 each for our dates.[:0][:0]
VH package prices with PE upgrades and looking very reasonable in comparison and PE is available. The hotel we had booked is also available.
Thanks
L2H