We just sailed out of Canaveral on the Harmony last week and they did care what your arrival time was. Upon arriving you were sent to the designated time line for your reservation.
Our time was 10:30 and we got in line behind the Suites. They also had marked separate lines for 11:00-11:30, 11:30-12:00 and 12:00-12:30. Those arriving for even later times than these were told they would have to go over to the sidewalk and wait….
Not sure what happened after we went in, but they were definitely checking.