It's good to have goals, but I don't know if I'd put a specific time limit on them. Our bodies have a way of losing at the rate that they are comfortable with and really don't know (or care) about time schedules and deadlines. Setting a time limit can leave you feeling defeated and like you are failing when you don't reach your goal on the date you set, even if you have been successful at losing weight (just not as much as you wanted).
When I first started low carbing, I did a lot of mental calculating along the lines of "let's see...if I continue to lose 2 lbs. per week, I can be at goal on this date...". It didn't work out that way, although I surely wish I could dictate to my body, "you WILL lose 10 pounds this month!" and have it happily oblige.
Set weight loss goals and celebrate when you reach them. One of the ways I celebrate is purchase a new item of clothing in a smaller size every time I can get into a smaller size (my goals are based on sizes, not necessarily weight loss).