I'm sure this has been answered but I couldn't find it. Ideally by what month of the year should one have his/her sfmatch CAS finished and submitted? Not the deadline, but the ideal time.
Sept 5th was the target date set by SFM for this year.
However, the advantage of sending in your application earlier (ie, mid-august) is that tends to get processed quicker (scanned and distributed to your program list) than if you send it along with the masses.