Robert Weede's understudy, Robert Rue (a student of Weede's), went on for Weede at the last New York preview, which was on Monday, October 9, 1961. According to a report in the New York Times, Weede had come down with "a respiratory infection and other inflammations." It was announced that the opening might be postponed till Friday, but Weede was well enough to go on as scheduled for opening night on Tuesday, October 10.
On September 4, 1962, Molly Picon started a 10-week a 10-week leave of absence to appear in the film version of Neil Simon's play Come Blow Your Horn. She was replaced by Hermione Gingold, who took over on September 4, 1962. Gingold continued in the role through November 10, after which Picon returned.
In his book Jerry Herman: poet of the showtune, Stephen Citron wrote that Picon’s understudy, Diane Goldberg, initially took over when Picon went on leave and that box-office receipts plummeted, and then Gingold was hired. This is not correct. In the issue of Variety dated August 1, 1962, it was reported that Gingold had been hired to replace Picon. This was then reported in the New York Times on August 3. Picon’s final performance before going on leave seems to have been on Monday, September 3, 1962. Gingold started the next day.