I just want to make you all really aware of the fact that the patronymics was rarely kept and if so used as a middle name sort of thing. Every emigrating Swede I have managed to trace (right) ended up being known by their father's surname, not their patronymic.
Example, sons and daughter of Johan Svensson who all was known for a few years in Sweden as Johansson all got the surname Swanson in America. I have seen this happening many times. I can not remember a single example where the patronymic was kept. Only family names like Cederberg and so on was kept as a family name.
On the subject of emigration dates that doesn't fit. It is simply either a completely different person you are matching to. Or the person took several trips to America besides the "final" voyage. Example a man went to America in 1882, without the permission of the parish priest by the way, returns ten years later, impregnates the family housemaid, probably can't marry her as he was missing for 10 years in America and can not prove he is fit to marry. She has another child, both getting American middle names, takes them probably another ten years to save up enough money to take the whole family to America and leaves Sweden and it's restricting rules in a cloud of dust. He has several immigration dates registered.
So, it's tricky but sometimes helpful that a person might have more than one immigration date, as the husförhör should prove the trips for you.
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