watchOS 5.3.3 (16U620) 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 29, 2019 Upload Date October 17, 2019 Filename 1dd30d61f7605e4cbfcfdb65cd9838409931b129.zip Filesize 1.4 GiB Identifier Watch4,3
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