OTTAWA GAMES WILL NOT BE BROADCASTED NATIONALLY.
Therefore, if you DO NOT LIVE IN OTTAWA and you have TSN, you still WON'T be able to watch the games.
Even if you have TSN, your TSN will play something different. Therefore your only choice is to move to Ottawa or to buy gamecenterlive/HS.
However, if you live in Ottawa, I'm pretty sure just need to go to TSN and you will view the Sens games as they will direct you there from their end.
My source is Brett Wallace.
So if subscribed to Rogers basic cable(carried Sportsnet but no TSN) , I'd have to upgrade to package that includes TSN to watch Sens games this season, correct?
Most likely. Although... Rogers basic should also have TSN... no? Here's what you do, call them and harass them to give you TSN. You shouldn't upgrade to bigger package that will cost you more for a channel that is known to be on cable TV.