Most Type 83 designs being shown came from potential manufacturers rather than the Ministry of Defence. They were proposals intended to attract an order, including ways to adapt a design the company already had. An extended Type 26 hull could offer a cost argument. Different hull-shape requirements could still justify paying for another design, so the artwork did not establish what Britain would actually build.
Notable Point · 3:30:22-3:31:13
Why Type 83 concept art did not settle the design
Manufacturer proposals could favor existing hull ideas even while the Royal Navy had reasons to seek a different shape.