I have found it useful to have time buffers for just about every task on my checklist. Depending on the complexity and uniqueness of the task, I buffer in the time anywhere between 15 minutes to a day in order to handle any changes that come my way.

I would keep them informed (maybe) some clients take change well and others don't. Some clients would see unexpected changes/chaos a lack in my event planning, so depending on the client, I would keep them informed if indeed it were to directly affect them or the budget. Event planners sometimes must make swift decisions in real-time and clients most likely either do not have time nor want to be brought into the problems (this is why I was hired or tasked with the job). Over the years I have found most clients during initial meetings typically state their "musts" so that I know what to do when they are not around, otherwise, they are OK with on-the-fly decisions I have made without them.

Communicate openly about any changes and provide solutions that uphold the event’s quality. Offer alternative options and reassure clients with a clear plan to address issues. Maintaining a calm, proactive approach demonstrates professionalism and builds trust during challenging situations.

The most thing I find useful is to go as prepared as possible to leave room for the unexpected. When chaos happens I usually try to stay calm in the storm and figure out alternatives when things don't go as planned. In that moment the client is grateful for any advice and solutions you have to save the event or manage damange control! Never lose your cool.

There are no events that run exactly as planned. Understanding that is the key to gauging your success of the event and to boost your mindset as these obstacles arise. Each event will determine how you approach the changes. Factors that can alter include the event type and the client’s perception of what is required of notification. As others have mentioned, communication is key. Prior to the event, assess potential changes and situations and meet with your client or host to determine what changes require immediate notification versus a post even debrief. Have contingency plans and escalation paths so that your team is aware of how to address changes.