watchOS 5.1 (16R591) for Apple Watch Series 4 (40mm) ✗ This OTA is not signed. OTA firmwares cannot be restored to. IPSW Downloads collects them for
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Release Date October 30, 2018 Upload Date October 22, 2018 Filename 93d1f8f6c15d8e9d50d5836218497dcb1b96d6ca.zip Filesize 1.3 GiB Identifier Watch4,1
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