FYI:
I found some info to start with on this standard motor club site:
31st December 1945 - The Triumph Company was acquired by the Standard Motor Company. A 4WD agricultural vehicle was produced based on the 8hp engine - only short production run.
1946
8hp, 12hp and 14hp continued as before now joined by Triumph 1800 in Roadster and Saloon form using engines surplus to Jaguars requirements.
Jaguar were now making their own cars of 2 1/2 and 3 litre capacity utilising their own engines, although they still used Standards 1 1/2 litre unit.
September 1946 - last years 4WD vehicle was replaced by the first of the Ferguson tractors.
1947
All models as for 1946 until July when the Vanguard was introduced originally in 1850cc form but soon enlarged to 2088cc with OHV gear.
1948
The older Standard models were now phased out, the last Eight being produced in July and the Twelve and Fourteen models ending their production runs between July and September. The Vanguard saloon continued as before to be joined by Vanguard Estate, 12cwt Van and Pick Up Truck versions in October.
Late in 1948 the Triumph Roadster and shortly afterwards the saloon were fitted with the 2088cc Vanguard engine.
1949
Production now was all Vanguard models and derivatives alongside Triumph Roadsters and saloons, the saloon becoming known as the Renown.
November saw the new Triumph Mayflower emerge with 1 1/4 litre side valve engine.
1950
The mixture as before with refinements:
The Vanguard was now available (in May) with a rolltop roof courtesy of Tickford and in June was fitted optionally with overdrive, as was the Renown, which had a new IFS chassis frame for good measure.
October saw the extremely attractive 'streamlined' Triumph Roadster, of which only 3 examples were built, as well as the introduction of a DHC of the Mayflower, again very short lived, being withdrawn in December.
1951
All as for 1950 but the Motor Show saw the introduction of a revised radiator grille and wider back window for the Vanguard (Phase IA as it is often termed) and a limousine option of the Renown.
1952
Again - all as before with the exciting addition of the Triumph TR2 sports, fitted with a linered down Vanguard engine of 1991cc plus twin carbs.
1953
In March, the Vanguard Phase II was released featuring a re-styled boot to complement the previous revisions of 1951. Triumph production continued as before. Ferguson tractors had been steadily produced in large numbers since 1946 both in petrol and diesel engined form, now, in September, Ferguson merged with Massey Harris, although the respected Ferguson tractor continued in both forms for several years to come. The 8hp Standard saloon was introduced during the year, a very spartan basic little car, with 803cc ohv four cylinder engine.
December saw the Swallow Doretti sports car based on the TR2, and produced by the Swallow Coachbuilding Co of Walsall and no connection with SS (now Jaguar) of previous association.
1954
Saw the introduction in April of the new Ten which had an enlarged engine of 948cc and a fully trimmed bodyshell with winding windows. This same bodyshell was used for the new Eight De Luxe which came out in June, whilst August saw the first Diesel engined Vanguard (with Ferguson motor) in Estate,Van, Pick Up and Saloon versions.
October spawned the Ten estate (Companion) as well as a 6cwt Pick Up based on the Ten. Flashing indicators, first seen on Beauvais' 1933 Avon Coupe were now fitted to the Eights and Tens. Otherwise the range continued as before.
1955
The Vanguard became the Vanguard III with unit construction body in place of the previous chassis framed vehicle. The 2088cc engine continued. In July the Family Eight replaced the basic Eight and for the Motor Show in October the Super Eight and Super Ten were announced with enhanced trim and equipment. The Motor Show also saw the introduction of the TR3, a revised TR2.
1956
The range continued as before, but the smaller cars were now joined in March by the Family Ten, a basic version, and the two pedal 'Standrive' system was introduced later in the year, again for smaller cars. The Vanguard III Estate Car, and the Sportsman version of the saloon (with basically a TR3 engine, albeit not quite as powerful) joined the saloon Vanguard III and the TR3 was treated to disc brakes.
https://www.standardmotorclub.org.uk/cars/standard_history.htm