fact: you can not make adjustments once the MASK is made. even if you were to run a gate/metal fix, you'd still have to run the whole process all over, which is a workflow of 2 month. This time is also completely not limited by man power, but limited to how fast the Fab can produce the layers, and this is not magic, it is mathematically calculable once you "tape-out", how fast you will get your chips back. all these are industry standard. TSMC, one of the big players in this field can produce a "super hot lot" in 0.8 days.
Note that this is effectively the minimum time. From what I've read TSMC and the other big players generally meet their schedules like clockwork but smaller boutique fabs tend to have more trouble giving a firm shipping date and sticking to it. I'm not actually sure why BFL felt using a smaller fab was something they should boast about...