For TATL *A awards I've booked through US, an hour seems to be a best case.

First, it often takes more than one call until you get an agent who knows the rules. Things like whether stopovers or open jaws are permitted, whether places like JFK/EWR are coterminal, etc, are important and some agents are flat out wrong.

Then when you think you've got a competent agent, you may not. In my case, I've had to deal with an agent insisting that my C award actually costs the international F mile rate because the domestic segment is F. And I'm told, "It's the computer, Sir. I can't change it, a supervisor can't override." Ok, thank you. Hang up, call back.

You eventually get a super agent, competent, knowledgeable and experienced with many award bookings. Once the itinerary is all set, you're still at the mercy of fare desks to calculate the tickets and fees. More segments and varying airlines tends to mean more time to calculate it out.

Read about some of the RTW awards people have booked, they've taken days to get a fare calculated in some cases.