Originally Posted by rossmacd

I understand, even though you are booked in a revenue bucket, the agent can see that you used some form of voucher to get there (this became apparent when I had to speak to BA about an itinerary that was booked in I then upgraded by a TA to A.. Therefore, I would expect that noticing this point would make your itinerary unable to be upgraded using Avios. Although, I'm hoping someone can confirm