Apple is offering watchOS 5 Golden Master for download this evening (build 16R364) at the same time as iOS 12 Golden Master (cf. iOS 12 Golden Master is available for iPhone, iPad and iPod touch).
As for iOS 12, it is a version identical to the final version which will allow developers and public testers to perform the last stability checks before September 17, the date when Apple will release watchOS 5 for the general public. .
To install watchOS 5 Golden Master on your Apple Watch, go to the Apple Watch app on your iPhone in the updates tab (My Watch> General> Software update), if you had installed the beta versions and follow the steps that appear on the screen.
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