Just got off the phone with AA phone agent and supervisor. Long story short: they would like me to pay full price for the ticket then mail in my vouchers to receive refund back on card once vouchers processed.
Needless to say I'm concerned about this approach as it flies in the face of previous experience and all the documentation in this thread. The reason being quoted is that I'm not flying on AA operated flight (my itinerary is YYC-LON on BA operated flight). I've booked and held on AA.COM and I definitely have AA flight numbers.
In addition, the address they've given for voucher mailing is different than the one quoted here and used previously (for AA codeshare flights I might add).
I have some comfort given that I was sent a direct email by the supervisor quoting their internal policy.
Thanks in advance for any help/advice!