Yeah I was wondering about that too, the website seems to act like just the support documents take three weeks "Support documents mailed to the SF Match may take up to three weeks for processing. Once all your supporting documents are marked as "Received," your CAS Application Form has been submitted, and you have created a distribution list and paid the distribution fees, your application shall be distributed to programs. Only complete applications are distributed to programs. Incomplete applications are placed on hold until made complete." So it would seem that you can wait on your CAS during that buffer time.
But the pdf instructions made me less sure - "During peak processing times, it takes up to three (3) weeks for your documents to be processed and distributed to the programs. COMPLETE applications will be processed and distributed in the order in which they are received. INCOMPLETE applications will be held until all required documents have been received."
I went ahead and pressed submit on my CAS when I saw that my docs were "received" yesterday just in case not having a "complete" application would slow my processing time, and now the CAS status says "uploaded" while the others still say "received." Lol so I guess that probably means that I could have waited on the CAS, but you might wanna confirm from an applicant from previous years if this buffer time is truly a buffer that won't slow your processing before taking advantage of it.
