I don't understand; you seem to have missed my point.
What makes you think that Freedom Shipyards was a civillian shipyard, anyways? And what makes you think it was building the Iceni before the rebellion started and the shipyard was captured (bearing in mind it's in Polaris, the first system to defect to the NTF)?
I think Freedom was a military ship yard, and I doubt the Iceni could have been built after the beginnings of the rebellion because it would have taken too long and cost too much for a rebellion that lasted on 18 months and probably didn't have the money to both build and design (from scratch) an entirely new class of warship. Modern day military equipment (warships, subs, planes etc.) take decades to design - admittedly, a lot of that could be stripped down, by eliminating testing, duplication of effort by conflicting companies etc. etc. but 18 months to build and design a 1 kilometer long warship using technology at least as advanced as that of the most modern ships in the terran fleet? And then fuinding it? R&D alone waould cost the equivalent of hundreds of millions of dollars - it's not something a rebellion can afford. Do you see the Tamul Tigers designing and constructing new classes of modern day warships in Sri Lanka? Or the Maoists in Nepal fielding next gen assault rifles? **** no. They're using stolen boats and AK47s. And yes, these are rebellions in less prosperous nations, but even so, the parallels are there I think.
To me, the only situation that makes sense in terms of the available timeframe and probably the available funds is for Bosch to convince the GTVA to fund and design the Iceni, and then pinch it the first chance he got.
Why would they have to design it
after the shipyard was captured. That could - and surely would have - be done before the rebellion took place, especially as it was solely a cover for the eventual deployment of the Iceni. So the 18 month figure (which IMO is likely as Polaris was first to fall) is solely for building the ship and, if it's using existing techniques, there shouldn't be a huge amount of research needed. Plus, I don't see the Iceni as being more advanced than, ooh, a Deimos. It's just differently specialised.
Plus, the likes of the Tamil Tigers, etc, aren't valid examples - these groups don't have anywhere near equivalent resources to the NTF; they don't have construction facilities, for example. Nor are they formed from defectors (IIRC) of regular armed forces, not to mention that the NTF would have likely gained ship design intel (if such a thing was not already available for the fleet's commanding admiral) from capturing said shipyards so they do not need to reverse-engineer to build new warships.
Remember, the NTF took Polaris - and then rapidly several other systems. Their resource base is completely incomparable to a domestic insurgency or guerilla war and something more akin to Texas declaring independence and being allied with by Florida & New Mexico.
Also, it's hard for me to see why the GTVA would want a ship like the Iceni.