No. Once the first batch has finished open the grill fully and remove the food. Close the grill and press OK. You do not have to switch off the grill first. When the lights flash again, choose the mode that you want. The preheating phase should be a lot quicker than the first time as the plates will already be hot. When the Optigrill beeps to say it is ready, open the grill again and put the second batch of food on to the plates and continue as normal.