TL;DR: If you enable the Time Ahead settings on the Apple Watch, it doesn’t move ahead in the rest of the OS. Is this intentional or a bug on Apple’s part?
Whenever people drive with me and we’re going to a movie or a concert, they're always get a little on edge. It has to do with the time. In my car, the clock is set 18 minutes fast. It's a mental thing for me, seeing the time of likely when I will arrive helps get places on time and not rush.
Before the Apple Watch, my wrist watch was ahead eight minutes. This, too, helped me get where I needed to be.
But I never set it up on the Apple Watch because meeting notifications helped me get where I needed to be. But last week, I moved the time forward on my Apple Watch.
When I was driving to the airport and listening to a podcast, I glanced at my watch and saw the Now Playing screen (the default in WatchOS 4. I noticed the time in the upper right hand corner was not what I thought. I pressed the crown to go to my main Siri watch face, the time jumped ahead eight minutes.
So it seems that the Time Ahead settings only apply to the watch face, not where time is displayed on other parts of the watch. This makes sense -- I don't want to get notifications eight minutes early -- but with the Now Playing screen a feature, it can get very confusing. I've looked at the time in this screen and thought it was eight minutes ahead.
I don't know if this intentional on Apple's part or a bug, but Time Ahead is getting turned off now. I'd like to use the feature but a watch with inconsistent time depending on what screen your in is no watch I want to use.