I was fairly, but not completely, convinced by spyfy's posting of the actual legislation that this would be the case, and that the phraseology on the application and in the instructions were not meant to imply that eligibility would be under the old rules. (Btw, a tweet is not a legally binding contract between IRCC and the applicant -- it is not legal advice and does not legally bind IRCC to a specific course of action.)
But because the phraseology on the application and in the instruction manual do, in fact, state that one must be eligible to apply the day before the application is signed, the prima facia meaning, whether intended by IRCC or not, is that one must be eligible under the old rules if one signs it on 11 Oct. For that reason, no one should be insulting OPs, or be short tempered with them, for interpreting IRCC's phraseology to mean exactly what it says -- and this has been my point since spyfy's posting of the legislation.