Let me see if I can help with several misconceptions appearing in this series of posts.
The use of dit names among French-Canadians is an often misunderstood custom. A dit name is a hereditary sobriquet, or "family nickname" if you like, that was originally carried by a specific individual in addition to his, or occasionally her, original family name. Dit names are passed down to descendents of that individual only, who continued to use these hereditary dit names with, or sometimes in place of their hereditary family names, as a demonstration of their ancestry. This continued until 1866, when the Canadian government required the use of a single family name. Thereafter, some individuals continued to use their hereditary family name as their only family name while other individuals chose to use their hereditary dit name as their only family name.
Since the use of a dit name with a given family name is properly used only by the descendents of the original bearer, it follows that a particular combination of family name and dit name appearing in an original family record indicates unequivocally that the individual in the record is decended from the specific original bearer, thus providing a very valuable guide in finding one's ancestors..
Note that it is important to confirm the use of a given family name-dit name pair from a reliable source and it is equally important to determine which is the original family anme and which is the dit name. (The information placed on the web by well-meaning individuals fails to recognize the significance or proper use of dit names and contains many errors, but original Quebec records rarely contain errors.)
The dit name Delorme, meaning "of the elms", is a fairly common sobriquet that was used by unrelated individuals from a number of unrelated families, including Lemay, Fafard, Enaud/Henault, Riel, Dube, Hazeur, and others. Note that in all cases, Delorme is the dit name added to the family name. (This situation is complicated slightly by the fact that Delorme can be a family name, not a dit name, in its own right, although none of the early immigrants to New France carrying this family name left male descendents.)
The Lemays of Quebec are descended from Michel Lemay, whose original family name carried from France is Lemay, not Delorme. Michel Lemay is my 7G grandfather. Thus, the Lemays of Canada were NOT originally Delormes. In fact, the vast majority of Lemays in Canada have never carried the dit name Delorme because the original bearer of this dit name was one of Michel's sons, Joseph Lemay dit Delorme. None of the other sons nor their descendents used the dit name Delorme.
Based on the above, I think that you can see that it is not possible for one of your Delorme ancestors to be a Lemay-Delorme and for his ancestors to be Dube-Delormes.
If your ancestor Alphonse Delorme does, in fact, appear in Quebec records with the family name Lemay, then his male ancestors must carry the name Lemay or the name Delorme, or both, and he must be descended from Joseph Lemay dit Delorme and from him to Michel Lemay. If not, then it still leads to one of the families above and, when a confirmed family name-dit name combination appears, you will know which one it is.
Unfortunately, knowing this does not provide the precise line to this original ancestor. However, knowing that this individual is your final goal does provide a direction to one's research. Anything that leads toward this destination has a high probability of being correct and anything that leads you away from it is almost certainly incorrect.
Please forgive this long response, but I've followed this exchange for a while and I just couldn't sit by any longer watching someone make a serious error in finding her true ancestors.