I've done some large scale grilling and here is my advice...DO NOT STOP COOKING....You'll have to use your best judgement here, but keep cooking...use some chafing dishes to one side of your grill to keep your excess warm and serve that out as you drop fresh grilled meat into the pan. You're gonna have to use your brains and eyesight to decide whether you need to throw 10 pieces on the grill or 20...but don't panic, evaluate the situation, and if someone has to wait 5 min extra for some awesome good food, so be it