First, lets make a difference between a "landscaper" and a "lawncutter"!! Landscaper does more then just cut grass, like pulling weeds, plant flowers etc, Feed lawn, spray for insects, so on, and so on. A Lawncutter cuts the lawn and sometimes edges, and blow debrees into your flower patch for weeds to grow>
But really, most lawncutters, don't do much in Dec-Jan-Feb if nothing at all. This time of year is when they sharpen up machines etc, so they are ready for March. It would be nice if they came Jan, just to do a nice edging job, and forget about mowing. (because it doesn't need it) But I pay them even though they don't come in Jan. They make up for it in spring and summer when lawn grows fast.