Marlins Lifer

I'm still pretty confused about all of this. (By the way, I've been following this awesome site for a while but this is my first post). As a DirecTV Choice package customer who lives in the local area, must I still purchase the Marlins.TV package? I called DirecTV yesterday and they told me I'd need to purchase this (from MLB, not from DirecTV) in order to watch the games this season. I was told the opener would be on channel 724 but I could only watch that if I purchased the complete MLB package. So I purchased the MarlinsTV $99 season plan (actually only activating the 7-day trial on MLB to test the water and have time to figure this out once the season started). I was able to watch tonight's game, which actually was on channel 655. My question is, would I have not been able to watch on ch 655 had I not signed up? I don't want to be paying for something that may already be included in my DirecTV Choice package (which I had long ago upgraded to specifically for Marlins/Panthers). When I signed up for Marlins TV on the MLB app, I assumed I would need to stream the games on my smart tv and devices, but seeing it right there on the DirecTV channel guide is very confusing. The representative I spoke with seemed very unsure himself. I don't even know if I would have to maintain the Choice package, since it now seems pretty useless, unless it is a requirement for being able to watch channel 655. Thank your for your time and nice to meet all of you, Dennis