Good morning Karen, I hope you had a great weekend! With regards to your question, currently there is not a setting or function that would prevent a user form making a change to an event at a certain point prior to the event. However, this is a great idea! Please add your suggestion to "Post Idea", located under the "Help" drop-down menu on the top right of your dashboard so that others within the system can vote on it. Our development team monitors these regularly and considers them for future enhancements, especially those with 30+ votes. We are grateful for all of our clients' ideas as they drive development, making us even better! Thank you.