I have a feeling they've fixed everything at this point. Meaning, I think u can do whatever u want, honestly. It should be creating a save point after every single play, actually. Therefore, u can close the app, or the server can crash, or u can leave in rest mode.
Although, I'll add this. In the situation I just tested, I quit the application because I'm still on ea access trial and I don't want to lose my trial. It's still possible, imo, if u simply left the game on, and walked away for an hour or so, perhaps the ea server would log u off, and that's where a potential issue can arise. U have PS4, so I'm not sure.
I'll say this as well for Xbox one, see, the other thing that can happen is switching apps or switching games. When u play another game, u sort of lose the last game's cached situation. I think that had something to do with my lost games in M16. Something about the caching of current game to allow u to switch between game and tv.
So, again, I'll say that based on what others are saying and my having just tested it with quitting the app (game), I think you're safe, overall. Hopefully, by now, they've accounted for all the types of scenarios how your system might shutdown or disconnect from ea servers. Perhaps, now, they ALWAYS create a save before anything can happen.
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