Attorneys for former Chicago police officer Jason Van Dyke are warning that the writ of mandamus the state is seeking to alter his sentence could affect his appeal.In a 13-page reply filed with the Illinois Supreme Court last week, Van Dyke’s lawyers said their arguments before the 1st District Appellate Court would change if the high court granted the state’s mandamus relief.Cook County Circuit Judge Vincent M. Gaughan sentenced Van Dyke to 81 months in prison after he was found guilty of the second-degree …