Venice, I am very familiar with your problem. I live part-time in EZE, so I check award availability (and fares) regularly ...

Part of my problem is the lack of inventory SFO-IAD. With currently only 1 wide-body (767) leaving SFO @ 7:40 am, there are only 319/20's and 757's on the route. The 767 seems to be the prime flight for business travellers (hence no advance award C/F inventory almost ever ...), and the Airbuses with limited F space (hence no advance award inventory almost ever ...). If you check award inventory IAD-EZE, you will see more availability (although UA seemed reluctant initially to make any new award space available once they discontinued MIA-EZE).

Previously with the MIA-EZE service there was a connecting 767 from SFO (and also another to IAD), but they are all history.

I have some flexibility in when I travel, so I have been able to book (and sometimes move) flights to something more suitable to when I want to travel. I book in F only when that is all that is available. There is really no substantial difference between C and F on a 767. And if you are on a narrow body to IAD, the most you get is domestic F anyway.

I have often booked a C award, with SFO/IAD booked in Y, since economy space is must easier to come by. No agent has been able to waitlist me in advance either for the domestic leg (although they tell me they have ...), nor have I been able to do it at check-in. I have ALWAYS had to go to the gate and get the agent working the flight to waitlist me ... go figure. Fortunately I almost always clear as a 1K.

It seems of late that UA inventory management is working the domestic flights in the weekend, and sometimes the day or two before. I always check at these times to look for, or change my existing bookings

It is indeed annoying to see award space open up for the outbound and NO return award space IN ANY CABIN for the next six months. Looking at the load on some IAD-EZE flights in the near future shows lots of revenue availablity (well it is winter there), in C/F.

Revenue seats are also historically VERY expensive at the moment. The lowest fares are often more than $1200 SFO-EZE, low season, and booked in S (so not SWUable). Grrrrrr.

Hopefully things will inprove with the return of ORD-EZE at the end of the year (but still a 767, unfortunately).

John