In my anecdotal experience, seemingly not noticed, as people assume that you came in just a few minutes before.

For a couple of reasons, I spent a period of time going into work at 6AM. Most came at 8 or 9. Far more people commented when I stayed until 6PM one day.

A former co-worker of mine used to do this as well. I didn’t notice for weeks and only because I logged in very early one day.

At my old job I was routinely praised for being a hard worker because people kept seeing me stay to 7pm. I usually heard comments like, "don't work too hard" and "make sure you don't stay too late".

What no one seemed to notice was I was coming in at 11. I never felt the need to correct anyone.

It’s also a great tip to work on your body language that says “I’m very busy with important things” even if you totally aren’t. For example, when you go to the break room or to sit on the toilet or to have a smoke break make sure you move very fast and purposefully from your desk so people think you’re just running back and forth to talk to people.

Also, don’t go anywhere empty handed. Always carry a clipboard or file folder with you to get donuts from the break room.

Smartphone works great for this in our industry. Be staring at it furiously typing as tho on slack/reviewing PRs while transiting to the shitter

Japanese workers have mastered this. So many people running about the office without actually going any faster.

If you want to be noticed, send out a few emails just as you get there.

In many clients you can program emails too, if you want to fake that. So it's not fully reliable either.

I'm always skeptical of coworkers who say they get in early. Some really do and are ultraproductive while others would say that but whenever I came in early they weren't there until much later. No surprise though: the former people were clearly productive and the latter ones were not. The hours aren't what really mattered.

So you keep tabs on your coworkers... you sound like a cool guy

Quite a bluff to pull: saying your starting early when you don't, when it's so easy to fall through. Does this actually happen?

In my anecdotal experience, arriving at work around 7 or earlier and leaving before 16:00 is absolutely not a problem. Arriving around 10 is also possible for those who prefer starting late. People try to group the important meetings in the middle of the day to accommodate everyone. Working overtime when needed happens but those hours can be grouped to take a few days off. I don't know if it is generalized but it's the case in the two companies I worked for in Germany.