Not sure about this. When I was on solo it didn't seem to skip but there were three of us on and it skipped with nobody admitting to sleeping.
Strange, I thought I sorted all the sleep logic out ages ago. Logging in/out and switching worlds triggers a check, but it should require at least 1 person actually sleeping to skip. I can take a look.
I did notice if you click a bed but it's too early to sleep it skips the night as soon as it gets dark without you actually sleeping.