Stanley, as I mentioned earlier, Olympic made her last sailing in March 1935; QM didn't make her maiden voyage to New York until 27 May 1936.
For an explanation of what all of this has to do with White Star, look here. Once the two lines' North Atlantic fleets were merged, the new company simply had too many ships---and in particular too many large ships. In fairly short order, White Star's Olympic (early 1935) and Homeric (late 1935) and Cunard's Mauretania (late 1934) were withdrawn, and by the time QM came along Majestic II (early 1936) was also gone, leaving only Mauretania and Aquitania to serve with QM.
There has been much discussion over the years about the factors that went into the decisions made by Cunard White Star and whether Olympic might have survived longer if White Star as an independent company had survived longer, but the fates of all six pre-merger large ships were directly affected by the merger.