Don't Install if You Don't have a Lot of Time
The watchOS 4.3 update takes a long time to install. We're not even halfway done with the latest version and it's taken nearly two hours.
Even after the initial rush to install watchOS 4.3 we expect that this update will take a long time to install because the process Apple uses is frustratingly slow and convoluted.
If you don't have at least an hour to set aside where your Apple Watch can sit on the charger and your phone can remain nearby, you should not attempt to install the watchOS 4.3 update.
The best bet is to attempt to install watchOS 4.3 at night when there is a long period for the update to complete.
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