What will happen with my app if I not get permission from FB to use "publish permissions"

I have a iOS application with more that 20k users. All current app versions are asking for publish permissions from user, but I never used it.

I'm already working on new version without this permissions, but I wonder what will happen with my app after April 30, 2015 without FB review? I don't have to go thru it if I'll remove publish permission from my app.

User can be still able to log in using facebook?

Mariusz