In this mod I propose to make 1 modest change by changing a date by 1 year and a second more ambitious change by changing one clause to read just a little differently.
1930 LONDON TREATY BEFORE TINKERING:
ANNEX I
RULES FOR REPLACEMENT
Section I
Except as provided in Section III of this Annex and Part III of the present Treaty, a vessel shall not be replaced before it becomes "over-age". A vessel shall be deemed to be "over-age" when the following number of years have elapsed since the date of its completion:
(a) For a surface vessel exceeding 3,000 tons (3,048 metric tons) but not exceeding 10,000 tons (10,160 metric tons) standard displacement:
(i) If laid down before 1 January 1920: 16 years;
(ii) If laid down after 31 December 1919: 20 years.
(b) For a surface vessel not exceeding 3,000 tons (3,048 metric tons) standard displacement:
(i) If laid down before 1 January 1921: 12 years;
(ii) If laid down after 31 December 1920: 16 years.
(c) For a submarine: 13 years.
The keels of replacement tonnage shall not be laid down more than three years before the year in which the vessel to be replaced becomes "over-age"; but this period is reduced to two years in the case of any replacement surface vessel not exceeding 3,000 tons (3,048 metric tons) standards displacement.
The right of replacement is not lost by delay in laying down replacement tonnage.
1930 LONDON TREATY AFTER TINKERING:
ANNEX I
RULES FOR REPLACEMENT
Section I
Except as provided in Section III of this Annex and Part III of the present Treaty, a vessel shall not be replaced before it becomes "over-age". A vessel shall be deemed to be "over-age" when the following number of years have elapsed since the date of its being laid down:
(a) For a surface vessel exceeding 3,000 tons (3,048 metric tons) but not exceeding 10,000 tons (10,160 metric tons) standard displacement:
(i) If laid down before 1 January 1921: 16 years;
(ii) If laid down after 31 December 1919: 20 years.
(b) For a surface vessel not exceeding 3,000 tons (3,048 metric tons) standard displacement:
(i) If laid down before 1 January 1921: 12 years;
(ii) If laid down after 31 December 1920: 16 years.
(c) For a submarine: 13 years.
The keels of replacement tonnage shall not be laid down more than three years before the year in which the vessel to be replaced becomes "over-age"; but this period is reduced to two years in the case of any replacement surface vessel not exceeding 3,000 tons (3,048 metric tons) standards displacement.
The right of replacement is not lost by delay in laying down replacement tonnage.
What this basically means is that all the following ships will be considered obsolete (and rightly so!) and therefore replaceable by 1936 (The year of the second London Treaty).
UK Hawkins Class CAs:
Effingham
Frobisher
Hawkins
UK "D" Class CLs:
Danae
Dauntless
Delhi
Despatch
Diomede
Dragon
Dunedin
Durban
UK Caledon Class CLs:
Caledon
Calypso
Caradoc
UK Ceres Class CLs:
Cardiff
Ceres
Coventry
Curacao
Curlew
UK Carlisle Class CLs:
Cairo
Calcutta
Capetown
Carlisle
Columbo
UK "E" Class CLs:
Emerald
Enterprise
US Omaha Class CLs:
Omaha
Milwaukee
Raleigh
Detroit
Richmond
Concord
Trenton
Marblehead
Memphis
IJN Nagara Class CLs:
Isuzu
Nagara
Natori
IJN Kuma Class CLs:
Kiso
Kitikami
Kuma
Oi
Tama
IJN Tenryu Class CLs:
Tatsuta
Tenryu
Now according to the section of the new 1930 Treaty above the keels of the replacement ships may all be laid down in 1933. If any keels are laid before 1933 then, according to the 1930 Treaty the cruisers above will need to be "disposed of" BEFORE the 1936 London Treaty. If everyone is smart and patient they wait until 1933 to start laying down keels so that when they go to the 1936 conference they have some more bargaining chips. Of course the 1936 London Treaty ends up regulating the size of individual ships in tonnage, BUT it doesn't regulate the total number of ships a navy may produce. So voila! The obsolete ships above are spared the scrap yard. The UK, US and Japan get to lay down some replacements as early as 1933 for some aging ships AND get to keep the ships they were intending earlier upon replacing!
I would think this might put the building schedules of the nations involved a little ahead of schedule if they can start a building program to replace these ships 3 years ahead. Perhaps empty slips could be filed a little earlier than anticipated.
I'll have to do a little more research to figure out exactly how to accelerate the ship building programs (and or if building programs could be accelerated), but concievably moving schedules ahead by 3 years might maybe lead to things like CL USS Cleveland being completed in 1939. Perhaps even some of the larger CLs or CAs could be converted into CVEs or CVLs relatively quickly.
