They're going to build at least 3800 of them (2443 for the US, 600 for the partners and 800 FMS).
That's what it says
here, and to paraphrase the Bard, Dr Thompson is an honourable man.
After all, he was the one who
assured us in November 2009 that everything was going just tickety-
ing-boo. And shucks, he had it pretty well right. Aside from the program office director getting canned two months later and the fact that it took more than three years before anyone could commit to an IOC date. Details, details.
The important point is that one must not underestimate the value of a paper commitment to a certain quantity of airplanes, because an irritating provision of Nunn-McCurdy is that it considers that naughty ol' PAUC.
So you might think that LM is sending Herr Doktor out to big up the production numbers and protect the PAUC estimate. But that's impossible, for Dr Thompson (as noted above) is an honourable man.