While the main focus of this product was on ships and other units that "never were" - be they "impossible" builds, or perhaps simply "unbuilt variants" - there are a few units which historically exist, and in a few cases might be more prominent now than when they were first committed to print.

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Perhaps the biggest case of this was with the Inter-Stellar Concordium's war cruiser and war destroyer.

In the original Module R9 setup, both the CW and DW were classed as "unbuilt variants" in Y170 - though they likely would have been built from that date onwards over in the "Mapsheet P" timelines - and became Regular Production Warships in Y189.

Since then, the R-section for the ISC heavy war cruiser further in Module R12 clarified that a "prototype" CW was built in Y187, so as to prepare the fleet yard to produce more in case this was necessary.

(No equivalent note was added for the ISC DW, though I'd argue that it would be "logical" for a prototype of this class to be made in Y187 also.)

Further, as these classes entered full series production in the wake of the Andromedan invasion, at least one new iteration - namely, the advanced technology war cruiser in Captain's Log #37 - was produced thereafter.

So, while some of these details are likely to be addressed in the pending ISC Master Starship Book, it might be worth factoring them "back" into this product also.

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Also, there happened to have been a "campaign conjectural" Neo-Tholian survey cruiser in this module.

Since then, the concept of there being Tholians in Draco has been added to the universe. As, indeed, has the existence of the Draco-Tholian survey ship Sojourner.

My understanding is that no final decision was made on what exactly the Sojourner looks like: either prior to its arrival in the Holdfast in Y195, or what (if anything) the local Tholians might have done to refit the ship thereafter.

Might it be worth considering whether the Sojourner was, in fact, some kind of NSR design - or, at least, whether it can be said for sure that it wasn't such a ship?