Actually I believe its error in the Master Parts Catalogue.
There are too many sources indicating that the SIIa didn't start until the 1962 production year.
From Grenville Motors allocations books we have 1961 SII models still available in the beginning of 1962.
When you use the Classic Land Rovers VIN calculator (which I believe is more accurate than CalVIN) you get it reporting SII models correct in 1961 and even giving a production number. The vehicle below is the last 1961 model in the Grenville books.
Chassis / VIN number : 143102230
Land Rover
Land Rover series 2 88"
Model 143 Series 2 88"
Body style Basic
Engine type 2.25l (2286cc) petrol
Market, Steering (3) CKD (Export), RHD
Model year 1 1961
Serial Number 02230 Number 2230 of 2302 numbered from 1 to 2302
Then we punch in the Snowy Mountains SIIa 88 mentioned previously and we get model year listed as 1962-1971. Even the suffix a is listed as October 1961 the start of the 1962 production year.
Chassis / VIN number : 24300001A
Land Rover
Land Rover series 2A 88"
Model 243 Series 2A 88"
Model year 1962-1971
Body style Basic
Engine type 2.25l (2286cc) petrol
Market, Steering (3) CKD (Export), RHD
Serial Number 00001 Number 1
Suffix A 1st revision of this model. Suffix used from introduction in October 1961 to March 1963.
When you replace the export market CKD "3" with the home market "1" you get the same model year information, except this time it lists the number produced.
Chassis / VIN number : 24100001a
Land Rover
Land Rover series 2A 88"
Model 241 Series 2A 88"
Model year 1962-1971
Body style Basic
Engine type 2.25l (2286cc) petrol
Market, Steering (1) Home market, RHD
Serial Number 00001 Number 1 of 42494 numbered from 1 to 42494
Suffix A 1st revision of this model. Suffix used from introduction in October 1961 to March 1963.
Even CalVIN agrees with 1962

