A state appeals panel on Friday called for an encore in the legal battle over the estate of the former Lyric Opera of Chicago CEO.The 1st District Appellate Court found the lawsuit filed by six of Kenneth G. Pigott’s children — after Pigott reduced their collective share of his estate to less than 50% — was timely filed.Former Cook County judge Karen L. O’Malley dismissed the lawsuit filed by petitioners Christine Brown, Ann Durham, Amy Pot, John Pigott, Steven Pigott and Katherine Pigott after …