The problem is that accurate shipping estimates and continuing pre-order sales revenues are incompatible concepts.
While this is largely true, it doesn't explain the inability to meet a solid target date for Batch 1. I think part of their problem is that once the date for completion of the chips slipped, any dates they had locked in for bumping and packaging couldn't be met and they then became dependent on those facilities being able to squeeze them in around other orders. They're not AMD or Intel, and this isn't a millions of chips run, so they don't have the kind of leverage to get booked orders bumped for their urgent run.
In their shoes, I'd forget about assembling back-orders in-house. Originally they thought they'd be able to quickly catch up on back orders if they contracted out assembly for batch 1 only. That's clearly not going to be the case - people ordering now are looking at a delivery date 2-3 months away
if everything goes well.
It's no longer clear when BFL might be able to make the transition to an order turnaround time of less than a week. They either need to stop taking new orders until they catch up or they need to accelerate their manufacturing process because inability to deliver quickly is going to affect the profitability of their units as everyone - including their own Batch 1 customers - brings more hashing power online.
It will cost them a lot more to accelerate manufacturing, but that has to be weighed against sales lost due to their inability to deliver units in a known, reasonable time-frame. A single ordered now could be worthless if delivered in June due to massive difficulty jumps over the next few months. It's probably not even worth keeping Jalapenos in their product line after the second batch of 6,000 chips is completed and assembled.