Originally Posted by
corporate-wage-slave
Depends if you are ticketed by CWT in the UK (Warrington) or by one of their other many business units. But assuming it is UK based, then UuA may work online, if not a call to BA should also do the trick. CWT don't do the Avios upgrade but they are able to see that it has happened since they lose control of the booking. For AUP, if it's a published fare then it's the same AUP process happens as normal, it can be done at the airport. I don't think POUGs can be done on CWT but since they use BA's booking process NDC directly but it maybe other FTers have seen this.
i used to work for a business that used HRG and I was able to UUA a flight By ringing BA. It’s the only time I’ve ever done this on a TA booking and it was about three years ago.