Originally Posted by
BingBongBoy
Just to point out...
Yes, you do earn TPs and Avios on Hotline bookings... However, under the Terms and Conditions of the Hotline scheme, you CAN NOT upgrade the booking using Avios. You may still be offered a PUO upgrade as it is treat as a regular commercial fare.
Just my experience but I've never not been able to UUA a hotline booking (excluding discount Y of course) - the online system link doesn't work but the call centre agents have always gotten it through.