Some of the information in those tables of serial numbers is absolutely not correct. First of all look at the NOC opinion of what the total production for 1961 is (228 bikes total?) compared to the other column. Also the first number for 1961 was in the mid 93xxx, much earlier than the figures they have here, I know because I have a 1961 bike with a serial number in that range.
I have also seen 1962 bikes in the 104xxx range, unless AMC was shipping bikes leftover from Bracebridge Street production out as their own 1963 production.
I have sent one Norton serial number to the NOC and to two other individuals with copies of the factory Norton records and got three different interpretations of what the records say about it. At one point the Science Museum in London had copies of the records for sale and several people bought them.
The NOC has their records split up between several individuals all converting them to digital media, with the liberties and misinterpretations I have seen from them in the past I don't know if I would hit a dog in the ass with anything they have to tell me.
Unfortunately it is all we have to go on. Those entire records should be released to the public to look at, but instead the NOC is charging ten pounds per to look up your number and give you their interpretation of their copy of the records, no thanks.