At this point there is nothing one can do about this. Dehydrating themself is about the worst thing they can do heading into I Day. They need to be eating and drinking. I don't even remember if we were weighed and taped on I Day. Maybe a current Mid can remember that. I don't remember anyone being sent home for weight on I Day, but I could be wrong.
For those who are over limits or will be pushing tape measurements... I know we hear a lot of things like I am a football player and I am really strong. Not saying anyone on this thread has said this, but battling weight issues as a Mid or Officer is not fun. If you are pushing the limits it only gets harder as you get older. USNA has done a better job of healthy options. If this looks like it might be an issue go see the nutritionist at USNA immediately. They can help you navigate food options and stay away from developing 'college food habits' of pizza, snacks, caffeine, etc. I have seen Mids battle this and it makes life so much harder than it needs to be at USNA.
Most will lose weight Plebe Summer. Some of the skinny guys might gain weight. But be cognizant of coming out of Plebe Summer you won't be burning Plebe Summer level of calories in the academic year (most won't... some athletes or those training for screeners might).