watchOS 5.1 (16R591) for Apple Watch Series 4 (40mm, LTE) ✗ 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 166ee2e9b239d84d595f7bc10604329b8d6c0de5.zip Filesize 1.4 GiB Identifier Watch4,3
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