watchOS 6 beta 4
Getting the error "Unable to Check for Update An error occured while checking for a software update."
running iPhone Xs and a Series 4 watch.
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One thing to note is that when the watchOS 6 b4 is installed it does not ask where you would like it installed and also does not force the reboot when installed. All prior watchOS updates required the user to pick install location as well as reboot the watch.