"Would have been beneficial to be informed of late running"

I accompanied a friend to an Outpatient Ultrasound Appointment. We arrived early and decided to have a coffee and go back to check in at the reception desk. We arrived back just a few minutes before the appointment time. 35 minutes after the appointment time my friend was called for their examination. There was no communication that there was any delay and the receptionist left their desk for about 20 mins leaving no one to welcome patients on arrival. 

It would have been beneficial to have been informed of a late running list. Instead the waiting room had a fair few patients who were frustrated as they were also well past their appointment time. 

Although we arrived early we had no expectation to be seen early, we had allowed plenty time to travel as we are from a distance to the hospital.