Growing up in Ontario I remember always being told we were in "Eastern Canada".
Growing up in Alberta, people often referred to Ontario/QC as "out east" and "down east." My brother still does that. And many people there seem unable to make a proper distinction between eastern and central Canada economically or politically too.
In my experience, Ontario and Quebec are colloquially referred to as "Out East" or "Eastern Provinces" while the Atlantic provinces are referred to more often as "The Maritimes" or the "East Coast".
Looking at a map, I guess I can see Ontario being close to central Canada (along with Manitoba and Saskatchewan), but Quebec is definitely almost as East as it gets, and since the data centre is in Montreal...
Ontario/Quebec are definitely commonly called "East" out here in Vancouver. The Maritimes are, well, the Maritimes. Central usually means the prairies.
Central Canada means Manitoba mostly, since it is geographic centre as well as being in central timezone.