After the first couple, you are instead called upon to lobby -- in other words, you have to contact the post and explain why they should take you on in whatever position it is they will have open. They look at performance reviews and recommendations, all kinds of other things, and decide amongst the people lobbying for the position which one will be best. At least, I think that's how it works. That's more or less what I've had explained to me.
Of course, you can't exactly rely upon what has been explained as the "official" process.
We made our second bid a few weeks ago, and on our end, things worked exactly as we expected. They send us a list of about 60 posts that would be opening, we did some research, tracked down some reports of what the actual posts are like, talked to friends or coworkers who had been to them, and set the list in order. They tell you to put about a third as "high," a third as "middle," and a third as "low." Good for us, because there were about 20 places on the list that we really didn't want to go to, for various reasons, and about 20 places that would have been great.
On a side note, that actually resulted in a strange moment, where we realized that no matter where we ended up, even if it was one of our "highly" desired posts, we would still have a period of disappointment... there would be at least 19 places that we also wanted to go. Even if we got the number one on our list, there would still be this twinge of "Damn. We don't get to go to ______."
We also submitted a short narrative description of what we were looking for in our next post. Things like a more moderate environment than our current post (where the temperature swings about 130 degrees between the hottest and coldest day of the year), or an easier language (perhaps one we had already put some time into, like Spanish or Japanese). You might think that no one would say "I want to go to a dangerous, disease-ridden post," but there are people who would relish the chance at adventure, and the +35% or more pay adjustment plus multiple R&R opportunities can really be a good reason to try those places out.
We submitted, and then nearly vibrated out of existence for a couple of weeks while we waited to find out where they would put us. They tell you that your current post matters - if you are in a "high differential" post, i.e. one that is very isolated, dangerous or culturally unfamilar, then you will get your preference, and if you are in a "low differential" post, i.e. one that is well-connected, safe, and familiar, that you absolutely should not bid on another low differential post, because you will just be disappointed when you don't get it.
Now, I know that there are a lot of variables that go into the person or people in DC deciding where each person is going to be assigned, but this experience has me more or less believing that the entire bidding process is basically just for show, and they are really just throwing darts at a map to see where they assign people.
Here's the initial disillusionment: nothing from the narrative explanation of where we want to go next was taken into account, as far as we can tell. And despite the fact that we are in a place with a comparatively high differential rating, we have been assigned to the post that was 19th on our list. Everyone we've talked to here got their top one or two. Now, I'm not actually disappointed, because we still got assigned to a post that we want to go to, and it's going to be great, but neither we, nor anyone we've discussed it with, can figure out how the decision was made.
It kind of seems like I'm splitting hairs, complaining about getting a post high on the list - maybe they thought it was close, and again, it was a place we told them we want to go...
But we weren't the only people in the process who got assigned inexplicably. And without getting into the personal details of those folks, some people got screwed hard, and some people got handed a second golden platter after the first. It literally makes no sense, if (and that is a doubly emphasized "if") they actually followed the process for assigning people that they had outlined to us. I don't think they did. The results don't match up with the explanation.
All of that is to say that if you end up joining the foreign service, do not count on the systems of bidding and getting post assignments to work exactly like you expect. You go where they tell you, and that's how it is. You could be fortunate, and go from one first world, Western country to another, despite the claim that that would never happen. Or you could be unlucky and somehow be shuffled around from third world hole to third world hole, despite the claim that that would never happen either.
That's the end of that rant, though. As I said, we did get a post we wanted: Beijing. And we have so many friends who have lived in China, who I'm sure are bursting at the seems about us ending up there, so we will have no shortage of help and visitors. My parents actually found out about this while they were hosting some new Chinese graduate students for a week before dorms opened up, and I'm sure that was a mess of excitement. It's going to be good.
I just wish we understood a little better why we ended up with that post. There are some people who have a reason to be upset, or to feel that the process was misrepresented. I feel sorry for their situation.