Just got back from a trip around the UK. Was told they would be using the staggered boarding schedule so was curious to see what would happen. We got to the terminal about a hour before our 'boarding time'. We are platinum level and were never asked about a boarding time. Went right to the platinum check in and then right on the ship. No waiting for our assigned time. From what I could see people who had not reached this level of sailing were sitting and waiting their time.