I don't think it makes much of a difference for people with adequate Step 1 scores, and it's probably of questionable benefit to "make up" for a sub-par performance, but one good option exists: take CK in late August, and turn your applications in when ERAS opens in mid-September.
At that point, your CK score won't be available so you can send out your USMLE transcript without worries. Once you get your score back in late September, you can decide if you want to re-release your USMLE transcript, including CK.
Programs will typically download applications from ERAS multiple times and applicants are able to login to see who has fetched their latest data. If a program you haven't heard from hasn't retrieved your latest info, you can send the program coordinator (not director) a friendly email saying your scores have been updated.
This allows the applicant to control what info the program sees. I pursued this route and while I don't think it made a bit of difference in my match outcome, it did give me a sense of security knowing I could either demonstrate improved performance or hold it back if I had done poorly.