Couple of quick and hopefully helpful comments.
Your kids can still qualify and get their awards no matter when they test during the year. It's just that if you don't register by the cut-off date, you don't get to attend the ceremony. You can confirm this, but I believe that's what I read.
As for online course prices: note that CTY Grade 1-6 math is EPGY. Only difference is that it's CTY rather than EPGY tutors, and CTY gives written exams and/or quizzes rather than online. If you want to save money on these courses, go directly to EPGY, where you can get them month by month (rather than $640 for 3 months). Maybe they have better aid, too. Don't really know.
Also, as discussed previously, you can go to
www.homeschoolbuyersco-op.org and watch the listings for Destination Math II and up which correlate exactly to Elementary Problem Solving I and II, Pre-Algebra, etc. Only differences (other than 8,000% discount) appear to be that CTY offers unit quizzes, written homework (which is actually decent for DM III/CTY EPS II) and tutors. Also, CyberEd courses are the CTY basic science courses. CTY requires 5th grade math, but so far there doesn't appear to be any math in either CyberEd earth and space science or life science.
HTH those concerned about $$.