(Bloomberg) -- The Biden administration’s program to send free Covid-19 tests to U.S. households informally launched on Tuesday to prepare for its official rollout on Wednesday.

The website to request tests, CovidTests.gov, is operating at limited capacity to accept orders. The early launch is standard practice to troubleshoot, White House Press Secretary Jen Psaki said Tuesday. 

“As you know, every website launch in our view comes with risks. We can’t guarantee there won’t be a bug or two,” Psaki said. “But the best tech teams across the administration and the Postal Service are working hard to make this a success.”

Households that place orders through the website or a phone line will each receive four kits, the administration said last week. The U.S. Postal Service will deliver the tests and expects the initial requests will be delivered in seven to 12 days.

The kits in the program are from the 500-million-test order approved by President Joe Biden in December. Last week, he said the administration is acquiring an additional 500 million tests. 

The moves came as the fast-spreading omicron variant has caused demand for tests to soar, leaving many Americans facing long lines at testing centers and empty shelves at stores selling at-home kits.

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