1) A "fab house" or "fab" does NOT assemble boards. They make chips. That's it. A "lot" or batch of chips takes somewhere between 4 and 10 weeks depending on the "process" (130nm, 65nm, 22nm, etc.) and how much the customer is willing to spend. According to Josh, they have paid the maximum for their fab to get them out ASAP. IF they are in 65nm process, I think this should be roughly 6 to 8 weeks - depending on which fab they are using.
2) Chips and other components are soldered onto boards at an "assembly house".
3) After BFL gets the "assembled" boards from the external assembly house (or done in-house in the near future), then they finish putting it together with heatsink and metal box then ship it out.
So go back and read the posts in this thread with the above in mind.
Disclaimer:
I have ordered a BFL SC Single.
I have ordered a 54Gh/s bASIC.
(I bought a ticket for each of the horses to win. )
You forgot 4) use the rig you paid for to mine a little bit, on the main net, under pretense of testing.