SACRAMENTO (KCBS) — With Covered California health insurance coverage beginning Wednesday, another hurdle for consumers will come on Jan. 6 when they must pay for it.

For the 400,000 Californians who signed up on time for the health care coverage, the state must receive premiums for that coverage by next Monday.

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That payment will provide retro-active coverage from the beginning of 2014. If consumers miss the deadline, they still have until March 31 to sign up without incurring a penalty.

“We’re still halfway through open enrollment. We’ve got three more months to go and we’ve got to keep the momentum going because we have millions of Californians without insurance,” Peter Lee, Covered California’s executive director, told KCBS.

Dr. Jonathan Weiner, professor of health policy and management at John Hopkins University’s Bloomberg School of Public Health, told KCBS that there will likely be glitches with the new insurance.

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“The first couple of months—it’s not going to be a pretty picture,” he said.

Weiner said, for instance, that medical providers may not be able to quickly verify coverage.

“The good news is that Covered California really is the leader. So in other words, the health insurance exchange done in the state of California, by all expert opinion, is really among the best,” he said.

Meanwhile, the Obama administration released their enrollment numbers over the weekend—about one million people have signed up.

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