EmberJS 2.11.0 rollbackAttributes throwing error

recently upgraded from Ember 2.4.x to 2.11.0 and I am having a problem figuring out what I did in the old that the new is complaining about.

thing = this.get('model');
thing.rollbackAttributes();

Can anyone enlighten me to the change that causes this and how I can use it properly? As far as i can tell I should not be seeing this issue. Clearly the Ember internals expects a property to be there. Its not anything I control but I sure would like to fix it.