Alfa skipped the 1968 and 1970 model years in the US. I think the official excuse was to adapt the cars to increasingly stringent safety/smog requirements, but these were non-existent in Canada before 1972. The reality may have been an overstock of cars by year end.BTW were 1970 Alfas imported at all to N America?? - I was told they were not. My scouring of the Toronto Star Classified rarely showed ANY '70 Alfas!-always a jump from '69 to '71s.
I have seen many 1968 and 1970 registered Alfas in Canada; I have owned a couple, but I have also seen a lot of Alfas from that period registered one or even two years after they were built! One club member had a "1971" roundtail...
Back then , it was not unusual for european car importers to redate cars at the end of the year. I have seen evidence of Fiat and Citroen doing the same.