ROSEVILLE (CBS13) — A large number of counties will be moving into the less restrictive tier of COVID-19 reopening, California public health officials announced on Friday.

Amador, Colusa, Placer, and Tuolumne counties will all be shifting down to the “Red” tier.

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California public health officials said part of the reason for the upgrade is because two million coronavirus vaccine doses have been delivered to some of the state’s hardest-hit communities.

Shifting down into the “Red” tier means that a host of restrictions can now be eased in those counties. Restaurants will be able to open limited indoor dining, among other changes. The shift will take effect Sunday.

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A total of 33 counties will be in the “Red” tier after Sunday’s change. Some 21 counties will still remain the most-restrictive “Purple” tier.

However, Sacramento, San Joaquin, Sutter, and Yuba counties are all also expected to move into the “Red” tier by Tuesday, public health officials say.

Yolo, Solano, and El Dorado counties moved into the “Red” tier earlier.

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Public health officials note that another update in California’s reopening blueprint will come once 4 million shots have been given out as part of the state’s vaccine equity quartile.