As a follow up, DFAS posted a pay statement on 16 Oct for my retro payment of CRSC monies, to be paid 21 Oct. Certainly good news for all concerned- approx 3 weeks to process after my first regular payment.
MSGHAWK, to answer your question, I mailed my CRSC package out in late July, was approved mid Sept, and first regular payment was Oct 1. My case might be atypical, as my listed conditions were previously adjudicated by the PEB to be combat related (during my IDES process). This may or may not have had an affect on processing time.