@KermMartian in fact I'm speaking about Jetpack 8x+. It's a port of an iOS game, but I already released it (even if I never released the source to anyone).
Yeah, then no, you can't use it now. Part of the requirement is that the program must never have been released to world before the contest ends, and that includes before the contest begins. Essentially, you have to have little-to-no idea about how it's going to fare against your opponents - and especially with Jetpack 8x+, you already know it will do quite well because it has been featured on ticalc.org.