Here is how I see the Hive Queen and Country timeline for tank development being different than Our Time Line
In OTL there were very few practical AFV attempts before 1898. Between 1898 and 1914 there were a few paper ideas (some including tracked suspensions) and some armored cars and mobile anti balloon guns all on wheeled chassis.
In 1914 the German advance was met by a number of Belgian, French and then British armored and armored cars and trucks. The utility of these machines was greatly reduced when the Western Front stabilized. From that point to 1918 six nations developed or attempted to develop all terrain armored fighting vehicles, Britain, France, Germany, America, Russia and Italy. Of these the first three actually fielded machines in combat.
The British developed their heavy tanks from MK I to MK V and Mk V*, with the MK II supposedly being a training machine only (although it was thrown into combat). They also produced the first self propelled guns The MK I Gun carrier which could carry and fire a six inch howitzer or simply carry a 5 inch gun, they also produced the MK I Medium Triton Chaser or Whippet, They also used older tanks as supply machines but developed the MK IX as the first purpose built APC. When the war ended there were two more Medium designs about to enter production as well as the International Heavy Tank. In this mix were a number of specialist versions, or normal versions equipped with special devices, such as devices for crossing wider trenches, ones to assist with climbing sea walls during amphibious assaults, some for commanders with large wireless sets, bridging tanks and recovery tanks.
The French had two heavy tanks based on the Holt tractor both carrying a hull mounted 75mm gun or howitzer. These proved somewhat less than effective, because of poor mobility and survivability and although later models had some modifications they were basically discontinued after the FT-17 entered service. This machine was the first service machine to have a turret with all around traverse, although Little Wllie had been planned to have one, as was the prototype of the Whippet (as well as a number of armored cars). The FT-17 quickly spawned a number of specialist versions including a command version. The base machine could either have a machine gun in the turret or a small 37mm cannon to fire high explosives. An assault gun version was also to be produced carrying the 75mm cannon. The French were prepared to temporarily use British heavy tanks until their own breakthrough machine the FMC-1 was ready in sufficient numbers, this was to be armed with either a 75mm or a 155mm howitzer.
The Germans produced the A7V, which also had two alternative versions, one a load carrier and another that carried two 7.6cm Anti Aircraft guns.
This means that between 1915 and 1919 the following types of machines were deployed or produced. Light tanks with machine guns, light tanks with cannons, Medium tanks, Heavy tanks with both machine guns or cannons, Assault guns, Self propelled guns, Self propelled anti aircraft guns, APCs, Load Carriers, Command vehicles, bridging and other mobility enhancement machines, and armored recovery vehicles.
Almost every important classification of armoured vehicles had its birth between 1915 and 1919. The only one missing is the dedicated tank destroyer.
In HQC the first armored fighting machines see combat in the Crimean. There is a period between 1854 and 1870 were very slow development takes place. The 1870 War of the Four Empires (France vs the Triple Empire of Spain/Portugal and Brazil) sees The Triple Empire field machines designed to hunt and kill the French siege diggers. The French respond with machines to protect their giant siege machines.
The British have basically ignored combat machines, but do have a number of tractors and such. Private industry produced a number of designs, without getting much interest from the Army, although the Royal Navy did purchase a number of amphib armored combat tractors. This lack of effective program lead to the failure of the Desert Column's attempt to reach Khartoum and rescue Gordon and his garrison. This failure in 1885 caused the British Army to develop first the MK I Fighting Machine.
The French Anarchist Revolution at this same time saw the revolutionary forces building a large number of improvised armored vehicles, since the Imperial Armored units initially stayed in their barracks. After the destruction of Paris by the Anarchists the army rallied behind Louis Napoleon and crushed the rebels, mostly using armored firepower.
The poor performance of British Armor and the effectiveness of French forces during a three year period caused tremendous concern within the British Press and Government. A Royal Marine "cutting out" operation against a French Revolutionary aerolyth base resulted in heavy casualties due to the combat value of the French machines and induced the Royal Navy to seek to improve its abilities. It also induced the Army to develop the Mk II Fighting machine, with its heavy armament of a 12 pdr QF Mk I*, specifically to be able to engage enemy aerial landing forces as they approach and right after touch down before they can disembark their troops and consolidate their landing head. These machines were just beginning to be issued to service units when the Anglo Hive War broke out.
In HQC the tactical and technological forces driving AFV development are very different than in OTL.
Terry