A limited work schedule (as banks were once known for having short work days and being closed on holidays and weekends). You won't be able to reach her on a Saturday—she keeps banker's hours.

A working day that is shorter than usual or acceptable, especially one that begins late and ends early. It refers to the traditional opening times for banks, which formerly opened at 10 AM and closed at 3 PM. With the boss out on vacation, some of us have been working bankers' hours for the past couple of weeks.