When did the hotel that hosted the recording of Farewell close?
July 16, 2007
Title: New Frontier Hotel and Casino
Passage: The New Frontier (formerly Last Frontier and The Frontier) was a hotel and casino on the Las Vegas Strip in Paradise, Nevada, US.  It was the second resort that opened on the Las Vegas Strip and operated continuously from October 30, 1942 until it closed on July 16, 2007.  The building was demolished on November 13, 2007.  The land is now owned by Crown Resorts who abandoned their project to build the Alon Las Vegas in May 2017 and put it up for sale.
Title: Farewell (The Supremes album)
Passage: Farewell is a 1970 live album by Diana Ross & the Supremes.  The album was recorded over the course of the group's final engagement together at the New Frontier Hotel and Casino in Las Vegas, Nevada, including the final night on January 14, 1970.  The show marked Diana Ross' penultimate performance with fellow Supremes members Mary Wilson and Cindy Birdsong.  At the conclusion of the show, new Supremes lead singer Jean Terrell was brought onstage and introduced to the audience.
Title: Valediction
Passage: A valediction (derivation from Latin "vale dicere", "to say farewell"), or complimentary close in American English, is an expression used to say farewell, especially a word or phrase used to end a letter or message, or the act of saying parting words whether brief or extensive.
New Frontier Hotel and Casino Farewell (The Supremes album)