Does Fluctuating Income Bounce Person's Coverage Between Medicaid and Subsidized Plan?

Suppose someone enrolled in Medi-Cal (California's Medicaid program). Later their income increased, and they became eligible to buy insurance in the Covered California health insurance marketplace, and did so.

If the person's income later drops low enough to again qualify for Medi-Cal, are they automatically switched to Medi-Cal at some point in time? In other words, is the marketplace insurance then suspended/canceled, or does the Covered California insurance remain active and they just potentially lose any subsidy?

I've read conflicting info about this online. Do you know of a credible

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