There is always more to do, in both work and life, than there is time to do it. You are expected to work diligently during work hours, and to limit your work hours in the ways you need to to maintain your mental health.
Within reason, you may keep the working hours that make sense for you, but keep in mind that science is a team sport, and you should endeavor to be available, at least some of the time, when others are working.
Minimally, you are expected to be consistently available for lab meetings, your periodic group meetings with Kevin, and any project-specific meetings, though in all of these cases, every effort will be made to schedule these in ways that accommodate everyone's unique schedules.
Kevin tries very hard to limit his own work to weekdays between 8am and 5pm. Members of the lab may choose to work in the evenings or on weekends in order to have more flexible schedules during the week, but no one is expected to do so. People working irregular hours should keep in mind that responses from Kevin will most likely be delayed outside of typical business hours.
Embedded note: Zulip
Time to rest and recharge is critical for physical and mental health. When you plan to be away for an extended time (more than ~2 normal work days) or during lab meetings/periodic meetings, please inform Kevin and anyone else that works on the same projects as you as far in advance as possible, and set yourself as away in outlook during that time.
Full time staff, students, and fellows have different requirements for reporting paid time off to the hospital. Please check in with Kevin if you do not know how to do this.