Let me start by saying I quite like Superbetter! Its a fun way to experience a new way of getting to your goals! However, I also found a way to "cheat". You may already be aware, but in case you are not:
On my way to my "epic win" I reached level 7 today and was wondering what those levels meant. I discovered the links to the secret files and new moves associated to each new level. However, I can also watch the future level achievements by changing the levelnumber in the URL on the website (I am using the website, not the mobile app).

For example, in my case I am a "level 7" and can see the associated moves and secret files at: https://www.superbetter.com/heroes/52023/levels/7.

But I can also see what my future has in store at level 8 or 9 for example by going to the URL:
https://www.superbetter.com/heroes/52023/levels/8
https://www.superbetter.com/heroes/52023/levels/9

There seems to be no check/lock mechanism on levels not yet unlocked.

Otherwise: this is great fun and me providing feedback should not be seen as criticism but an enthousiastic way to contribute to a better superbetter :-)