Office building with dining facility

We are working on the design of an office building where there is a conditioned dining area for office workers and visitors. The dining facility has the capacity to accommodate 280 people. The design team and the owner have told us that the expected occupancy will be: from 11am to noon: 60 occupants noon - 1pm: 250 occupants 1pm - 2pm: 136 occupants 9pm - 10 pm: 88 occupants 10pm - 11pm: 88 occupants All other hours it is expected to be occupied by 14 people - 5% of maximum occupancy (for meetings, coffees or resting) For the VRP calculation shall we use the maxium occupancy of 280 people or can we use an average for the maximun occupied time (11am untill 2pm), which would be 149 occupants? If we use the equation 6-9a, the averaging time period is 0.76 hours. Thanks in advance, Anderson