>>30916194Well, I eventually landed on the frame I was going for (344) through trial and error.
Still, there seems to be some odd quirk with it, as the frame I accepted the egg on should have yielded a different spread. I accepted it on frame 314, and somehow it shot all the way up to 344 and gave me the shiny spread there. According to the jap guide/jap program, accepting an egg on frame 314 should advance the RNG to frame 349, so I really don't know what to make of this.