Merry Christmas!
Smurf sent me a couple of line drawings a few weeks ago of proposed light cruisers from the DNC dated 1918. The main change from the D and E series was that the cruisers were to be armed with the same single 7.5" as fitted to the Hawkins class cruisers. Two types were proposed, one with 4x7.5" with dimensions of the E class, while a larger ship of 602 ft armed with 5x7.5" was the second type. Both ships looked like the E's in their superstructures and fittings, with appropriate changes required by the larger guns. (Which has meant I have been able to utilise a lot of parts from my E series.)
This is the first one with 4x7.5" which I have called HMS Triumph after the pre-dreadnought sunk at the Dardanelles.
I have been re-reading my notes on the E's. The E's were laid down in March/1918 so these designs post date those ships final designs. Which is probably why the designs look a lot like the E's. Once the end of the war came in November/1918 I can not see any of the two designs being proceeded with. As it was the E's were cut from 3 to 2 at wars end.
The 5 gun version had dimensions of 602x57 feet, the extra length being directly taken up by the compartments required by the center mounted 7.5" gun. That gun was mounted an extra deck higher than the main deck. The same bow and stern of the four gun version was kept. Superstructure items and torpedoes were moved around like Lego pieces and ended up in different places on the ship.
The name Formidable now given to the 4x7.5" ship is also from a pre-dreadnought sunk at the Dardanelles, while the name Fearless is from one of the 1904-05 Scout cruisers that were discarded and sold in 1920-21.
Below is the six gun version I recommended in a later post.