Most hybrid mattresses should not be flipped. A traditional hybrid features layers of cushioned material and layers of springs, carefully arranged for optimum comfort. When you flip the mattress, you upturn the order of the layers. At best, you'll make the mattress uncomfortable to sleep on. At worst, you risk causing serious damage to your bed.
Note, we're talking about turning the mattress so the bottom becomes the top and vice versa. You might still need to rotate your hybrid mattress (so the foot end becomes the head end), but instructions for that will vary from model to model.