I'm not 100% comfortable about the meal plan of 1,000 calories a day. Even if it's for a week or two max. Mainly though the Green Tea with every meal, will potentially create a fairly high Caffeine dependancy by the body and if you cut back quitye a bit to say 2-3 cups a day, you'd possibly be getting mad withdrawal symptoms potentially.
Especially as the Xanthines in Caffeine can be converted to Uric Acid, which along with the Nitrogen in Protein, could elevate Gout risk, so perhaps consider limiting the Green Tea, as it will probably work mostly as a diuretic anyway and then your body won't develop a liking, for a bit too much of the stuff

.