watchOS 6.3 (17U216) 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 January 26, 2021 Upload Date January 14, 2021 Filename 5e35b2a4354205dccbdbc58e2975d1dd7d7c3c24.zip Filesize 1.4 GiB Identifier Watch4,1
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