I've searched and have not found this feature or how to do it. My setup is this (with a Pro account). I have 7 folders syncing between several machines. 5 of them rarely change and are all synced up and only increase in size once a month or so. One folder is used to back up all my machines throughout the day, this folder constantly changes. And one changes daily, but is not relavent to my question. The back up folder I would like to have it sync during the night while the other 6 can sync constantly. Since 2 of my machines are at work, when they sync during the day it saturates our connection. My solution so far has been to limit my speeds during the day and unrestrict it at night. This works, but is tedious, and if I forget it's either throttled all night, or Internet at work is slow until I get in.
