Autosave Issues

[BossHaas]

After my first playthrough on Normal, I started another playthrough on Supernova. I was about halfway through the campaign when I decided to go back to my first character and get some trophies for PS4. After an hour later, I decided to go back to the Supernova Character only to find it was overwritten by the 1st character. I realize this is my fault because I never took the time to hard save the game. Instead I always let the Autosave do the work. (Forgot what I learned about saving the game when playing Mass Effect 1) There needs to be a better way to save in SuperNova difficulty than only allowing it on the ship. And along side that, the Autosave feature SHOULD be different between characters. Autosave SHOULD NOT be shared between characters. This is the problem I ran into. Is there a way to make it so that Autosaves dont overwrite autosaves from other characters?