Yes, this is very confusing. Some people could read this and mistakenly assume that their reflections are always kept secret (because they didn't read the second sentence).
It might be better to change it to "Reflection are kept secret until Sunday."
This might seem like a little issue, but it's not. All it takes is one over eager person to join the app in haste, not really read how it works, post some embarrassing secret thinking it will be kept secret and then become mortified when it's revealed. Then they will raise a storm online and your app will be known as something that causes drama rather than alleviates it.
It might be better to change it to "Reflection are kept secret until Sunday."
This might seem like a little issue, but it's not. All it takes is one over eager person to join the app in haste, not really read how it works, post some embarrassing secret thinking it will be kept secret and then become mortified when it's revealed. Then they will raise a storm online and your app will be known as something that causes drama rather than alleviates it.