People I met on RS tours who liked to sleep in later often came down for breakfast at the last 30 minutes. They'll have a cup of coffee or juice, then take a piece of fruit and a breakfast roll/other and pack it in a baggie. They'll eat it on the bus. But this idea doesn't work well for days your group has a morning walking tour or you're off to Museum.
The earliest days departures for this tour are the days 6 and 8 when you are sight sighting in route to your next destination.
Day 2 is close to *815-820am departure as you're taking a train to Brussels for the day. The other mornings are 830-930 departure days. Day 5 is a free day so you could sleep in that day.
On Bus days the driver must stop after 2 hours. So you'll have another chance to buy a snack and beverage. Also, the drivers have water, beer, and some soda each day to buy on the bus. Also, as Stan said, you can nap on the bus.
The daily itinerary is designed to avoid the heavy tour crowds, congested traffic areas on the roadways. RS brand prides itself on avoiding the queue. Personally, I found it refreshing and appreciated not being overrun by other travelers.
Bruges was the only base where the bus could drop and pick us up closest to the hotel.
Whatever you decide just be downstairs and ready to go on time!