Nothing is changing for satellite, this only applies to streaming via the app and online. On satellite EI is mostly remaps of RSNs (and repurposed CINEHD channels for part time and non-carried channels), so the corresponding RSNs in the 600s get opened up for you during games, while non-EI subscribers with Sports Pack get a call to subscribe message during games.
On the app, if "YESOM" is available and you selected 631, with sports pack you would see filler like Tennis, Beach Volleyball, NASCAR Rewind or Poker instead of the Yankees, Nets and Liberty games. You will still be able to watch the pregame and postgame coverage along with the Michael Kay Show, and classic games from previous seasons are available.
Only the Bally RSNs and YES have their localized feeds on the app. The rest of the RSNs use the same streams nationwide, but have blackouts during games, so even if you subscribe to Extra Innings + Sports Pack, you still have to use MLB.TV to stream the out of market games.