watchOS 5.3.6 (16U662) 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 March 24, 2020 Upload Date March 19, 2020 Filename f2cb54a27fc4d859ca1bf3fcf685c97062559a45.zip Filesize 1.4 GiB Identifier Watch4,3
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