watchOS 5.3.6 (16U662) 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 March 24, 2020 Upload Date March 19, 2020 Filename d1d2c2320b76c11282a9d62d24c3797afba02fb8.zip Filesize 1.3 GiB Identifier Watch4,1
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