That's 145 days, if you cut down to 1500 calories you can create a deficit (at 5'1 500lbs) of 2100 calories a day. 304,500 calories would translate to roughly 87 pounds. I'm sorry, but it's just not possible... safely at least.
If you're serious, I'm going to need you to cut down to 300 calories a day, and start ingesting 25mg ephedrine, 200mg caffeine, and an 81mg st joseph enteric coated aspirin every 4 hours, from now until July. That's also not going to be enough unfortunately, so you need to start exercising. I suggest 3 hours of elliptical cardio a day.
You can do it, don't give up.