Huawei is rolling out the March 2020 security patch to the Huawei Nova 3 and Huawei Y9 2019. Huawei Nova 3 is receiving March 2020 security update with EMUI 9.1.0.366 an upgrade from EMUI 9.1.0.360 and 255MB software size (via Huawei Central).
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While the Huawei Nova 3 is receiving the March 2020 security update with EMUI 9.1.0.264 and a software package size of 97.15MB (via Huawei Central).
The March 2020 security improvements including Google security patches and fixes for 2 critical and 20 high levels of Common Vulnerabilities and Exposures (CVE).
Note: The update is rolling out in batches, so it may take some time to reach your device.