Due to change in plans and coronavirus I have had to cancel a 241 booking for which I have now received all the required refund and avios. I am now going to rebook and I thought as I am actually out of my home address during the 355 day window for the outbound flight I would try to use the the online booking method. This is an open jaw flight that I believe meets the distance criteria, flight would be out to Vancouver in PE from Jersey and then back some weeks later from Tokyo in club. My intention was to do the following.

Book the Jersey Vancouver online using the 2 4 1 voucher. Then, when I get home ,and the 355 window opens up for Tokyo, I was again going to book Tokyo to Jersey online as the fees and charges are substantially less from this destination as a one-way booking. This would be of course using double avios points for the two passengers as it would not at that point be part of the 241 booking. I then understand that I can phone BA and ask them to put the two bookings together under the original 2 4 1 voucher and half the avios for the the Tokyo Jersey sectors will be refunded to me. Can someone please confirm that my understanding of all of the above is correct and then I will put the plan into motion at the appropriate time.