Diana Nyad is back at it again -- once more in the water off Havana and heading, she hopes, to Key West. The 62-year-old endurance athlete jumped in waters off Cuba at 3:42 p.m. Saturday, one day earlier then she and her Xtreme Dream team had originally planned, according to her Twitter page. If all goes well, she will swim some 103 miles and for perhaps 60 hours before arriving in the Florida Keys.