Hundreds of thousands of Californians could soon find themselves in health care limbo as federal insurance subsidies edge toward a year-end deadline. Covered California says nearly two million people rely on the exchange during open enrollment, but no one in Washington has confirmed whether the extra Affordable Care Act help will continue past December 31. The agency warns as many as 400,000 consumers may abandon their plans or be forced to look elsewhere if Congress fails to act. Without an extension, families could see steep premium hikes or lose coverage outright.