If the earth's direction of rotation is reversed, what would be the IST when it is noon at the International Date Line?

India is a large country spanning over 30° of longitude. It is unusual in having a single time zone all over the country, 5½ hours fast. If the direction of rotation of earth is reversed then Indian Standard Time will be – 5½ hr. When it is noon the time is 12:00; that will be 6:30 A.M. in place of 17:30 P.M. or 5:30 P.M.