Just as an info point . I booked a F/J ticket CAI-BKK last week . Before booking I checked that Award ticket Availability was available in First for the DOH-BKK-DOH legs . I also saw that both First cabins were showing empty . I bought the ticket and applied to upgrade the 2 sectors from J/F using 60 Qcredits using the online form .

As seems normal I got an "unable to process your request" ,so I tried again and got a "You have already applied for this upgrade" . Activity was showing redeemed for upgrade baggage allowance some random characters and a deduction of 0 Qcredits .

I waited 24 hours and was sent an E Mail saying the upgrade request was refused . As the cabins were still completely empty, I replied to the email asking why it was refused . Later in the day I received a second Email with both upgrades accepted ,Qcredits deducted and ticket re-issued .

Now I'm not sure if this means that Upgrade availability is not the same as award availability or if its just QRs clunky upgrade request webpage . Its maybe better to call your local office for upgrades than using the online form .
Only problem is if there is a change in taxes , the local office cannot take payment over the phone (or at least in Egypt they cant ), so you need to call Doha to make the payment .Thankfully there were no additional charges for me this time.