United Airlines Disappointing

We booked for our daughter to fly to America with United Airlines on 26th December departing today 11th January 2022. Woke up this morning to an sms advising “we need to take the plane out of service to address a technical issue”.

We frantically began calling as it has huge impact on further travel plans in America, cost implications & the Covid test results window. Seems the plane is simply not full enough so is not flying but instead she is being bumped to tomorrow night with little regard from the airline for the impact this has on her or us (and ALL the other passengers who were booked to fly tonight on the same aircraft).

Now we need to fork out more money for further COVID PCR testing etc. - and this kind of service leaves us wondering how the rest of the trip will go with United if this is just the beginning experience?