OMG, another game restarted.
In my defence the game shows the old savings.
I assumed since you had an old save from playing the previous version, that you were following this thread. And again, assumed you knew the news about what was going on with this game.
Your saves still show up because the game itself is still the same game (Lust Campus). It loads/saves to the same spot still, so your saves will still be seen since the game itself didn't change.
The content however is completely different. The game had to be remade. It wasn't something they chose to do, it was something they were forced to do. The old artist abandoned the project and wouldn't let them use the art anymore. So they had to remove it and start over again. It was a rather large ordeal here and was saddening to hear. They had no choice. It was either start over or scrap the game (which they were close to doing).
But a new artist stepped up and joined the team and they worked together to bring the game back to life. Even though it meant having to redo all their work over again. But in the process they were able to use this opportunity to make some changes to the story to make it better and add some new content as well (like the addition of a new character in the first chapter).
Yeah the old art style is going to be missed (like, a lot lol), but this new art style has it's own charm. The backgrounds definitely look better and have more detail. Just the characters themselves are going to take some getting used to. But they do look good still. Again, think it will just take time for a lot of us to get used to it.
But hope that helps you understand why it was restarted.