I haven’t read the article — no magazine yet here.
Costco Premium and Ultramar Premium are both ethanol free(Costco everywhere I think– Ultramar certainly where I am). Shell Premium I am not so sure is ethanol free everywhere (at least where I am the pumps don’t indicate it so) so that may be station dependent.
The problem with Ontario is that it is a requirement that gas stations average 5% over all retail sales so you never really know what percentage ethanol (or even if there is any) ethanol when the pump is labelled “may contain 10% ethanol). My understanding is that newer Porsches are OK with ethanol but older (not sure where the cutoff is -1996 and water cooled?) cars Porsche has indicated should not use gasoline with ethanol.