From what I have heard, part timers are all ranked together, and full timers are ranked together. They do not combine the groups at any time because it would not be fair to either group. As you go through school you will only be ranked with the group you began with. For example if you are a 2nd year part time student, you would only be ranked amongst the other second year part time students. You would not be ranked amongst all part time students.
I believe if you switched in to full time, you would get ranked with the full time students, and vice versa.
Wharfrat, I think that decisions on law review would be made before you finished your classes in the summer, I think you would still have to wait out the year, but I am not certain. You should call the schools you applied to and see what their policy is for that.