▁ ▁Effect ive ▁date . ▁ ▁Ex cept ▁in ▁extraordinary ▁circumstances , ▁the ▁rule ▁does ▁not ▁become ▁effective ▁for ▁some ▁time ▁after ▁its ▁initial ▁publication ▁to ▁allow ▁reg ulated ▁parties ▁to ▁come ▁into ▁comp liance . ▁ ▁Some ▁rules ▁provide ▁several ▁years ▁for ▁comp liance . ▁ ▁" Hy brid " ▁rule making . ▁Not ▁a ▁legal ▁term ▁of ▁art , ▁but ▁describes ▁the ▁kind ▁of ▁rule making ▁performed ▁by ▁ag encies ▁that ▁is ▁somewhere ▁between ▁formal ▁( with ▁a ▁hearing ▁and ▁record ) ▁and ▁inform al ▁( with ▁the ▁notice ▁and ▁comment ▁procedures ▁described ▁above ). ▁ ▁Hy brid ▁rule making ▁generally ▁sub sum es ▁proced ural ▁aspects ▁reserved ▁for ▁adj ud ic ation , ▁such ▁as ▁a ▁formal ▁hearing ▁in ▁which ▁interested ▁parties ▁are ▁sw orn ▁and ▁subject ▁to ▁cross - ex am ination . ▁ ▁The ▁stat ut ory ▁construction ▁of ▁the ▁Administr ative ▁Pro cedure ▁Act , ▁as ▁well ▁as ▁the ▁Supreme ▁Court ' s ▁r uling ▁in ▁Verm ont ▁Yan kee ▁N uc lear ▁Power ▁Cor p . ▁v . ▁Natural ▁Resources ▁Def ense ▁Council , ▁Inc ., ▁make ▁hy brid - ru lem aking ▁proper ▁only ▁when ▁specifically ▁provided ▁for ▁by ▁the ▁U . S . ▁Congress . ▁ ▁In ▁the ▁United ▁States ▁when ▁an ▁ag ency ▁publish es ▁a ▁final ▁rule ▁generally ▁the ▁rule ▁is ▁effective ▁no ▁less ▁than ▁thirty ▁days ▁after ▁the ▁date ▁of ▁publication ▁in ▁the ▁Federal ▁Register . ▁ ▁If ▁the ▁ag ency ▁wants ▁to ▁make ▁the ▁rule ▁effective ▁sooner , ▁it ▁must