The latest Miss Trunchbull's arrival was delayed for a month because of an injury.
The two Broadway veterans will take the stage at Sardi's on April 23.
Sieber is now expected to begin performances as Miss Trunchbull in April.
The Broadway musical plays the Shubert Theatre.
Two performances will take place on January 26 at XL Nightclub.
The two-time Tony nominee will offer a pair of performances at the Broadway supper club next month.
American Repertory Theater has announced casting for its second production of the 2013-14 season.