When there is a material change to these Terms of Service, you will be notified of such changes the next time you sign on to ClassFlow. If you choose not to accept the changes, you will not be able to continue to use ClassFlow. 21.2 If you are an Enterprise User with a subscription to the ClassFlow for Schools Service, you will be subject to the policies and terms and conditions in force at the time that you register with our Service, unless any change to those policies or these terms is required to be made by law or governmental authority or we notify your school or district in writing of the changes to those policies or these terms and conditions.