OK here's a data sheet on the current British tanks. Named after weapons, except the Matilda (as its basically the same tank, it would have been confusing to rename it).
Two are basically very similar to OTL, the other 2 should have been straightforward to build. Ironically the two Vickers designs are very close to the Pz III(with the 5cm gun and thicker armour of Autumn 1940) and the Pz IV (with the thicker armour of late 1940), both of which could easily have been produced in 1939.
British Tanks, comparison with OTL tanks
Vickers A10* (Sabre) Mk3
HV3pdr gun, 50mm frontal armour, 35mm sides. 360hp diesel engine, speed about 20mph/28mph(road). Modified 3-wheel 'slow motion' Horstman suspension. About 20 tons.
In British terms its similar to the Crusader tank
Crusader tank - Wikipedia. Its also similar to PzIII Ausf.H
Panzer III - Wikipedia
Vickers A11 - (Cutlass) Mk 2
6/18pdr gun, 70mm frontal armour, 60mm sides, 360hp diesel engine, speed about 14mph/23mph(road). Horstman suspension.Weight about 25 tons
No real OTL British equivalent, operationally is a faster Matilda with a bit less armour. The closest OTL tank is the PZ IV Ausf.F1 or Ausf.E
Panzer IV - Wikipedia
Vulcan A12 (Matilda) Mk 1
HV3pdr gun, 78mm frontal armour, 70mm sides, 190hp (twinned engine), speed about 9mph/16mph(road). OTL suspension. Weight about 26 tons
Basically this is the OTL Matilda II with a 3pdr gun.
Matilda II - Wikipedia
Nuffield A13 (Scimitar) Mk 2
HV3pdr gun, 30mm frontal armour, 15mm sides, 320hp petrol engine (Liberty), speed about 24mph/30mph. VVSS Horstman suspension.
Most similar OTL tank is the Cruiser Mk IV
Cruiser Mk IV - Wikipedia the differences are the HV3pdr gun and the different suspension system. Has the same wonderful *cough* Nuffield Liberty engine. About 16 tons
Guns.
The HV3pdr is an enlarged 2pdr. Something similar to
4,7cm KPÚV vz. 38 - Wikipedia or
47 mm APX anti-tank gun - Wikipedia. As it can use the older 3pdr ammunition (at a lower MV), it does have an HE shell, even though it's not brilliant
The 6/18pdr is based on a Vickers 6pdr naval gun, lightened a bit then 'throated out' to handle the 18pdr shell. It has an AT round, but this isnt as powerful as the 18pdr artillery one, but its still good by 1939 standards
The Kiwi engine is a diesel based on the RR kestrel, a simplified version of one built for a racing car.
The Sabre Mk3 comes in Autumn 1939 (the Mark 1 finishes production Summer 1939)
The Cutlas Mk2 comes in Spring 1939
The Matilda starts arriving in Summer 1939 (in small numbers, production issues as OTL)
Scimitar Mk2 starts arriving in Spring 1939