Labor never held Congress under President Adam Griffin.
Conservatives (Feds+CR) won a majority in August 2015 and held it through the reset.
Last Bore Congress
https://uselectionatlas.org/AFEWIKI/index.php/Sixty-Ninth_SenateCongresses under Adam
https://uselectionatlas.org/AFEWIKI/index.php/Seventieth_Senatehttps://uselectionatlas.org/AFEWIKI/index.php/Seventy-First_Senate72 and 73 don't have pages unfortunately, but in February 2016 the Senators elected were
South: PiT (F)
Pacific: Dereich (F)
Midwest: Potus (F),
Mideast: Dar (Lab)
Northeast: Blair (Lab)
And April 2016:
Seat 1: Clark (F)
Seat 2: JoMCar (F)
Seat 3: Leinad (F)
Seat 4: CXSmith (Lab)
Seat 5: Truman (Lab)
The Laborite victory in the House in August 2017, was the first left majority in At-Large seats since the April 2015 elections and first laborite majority since Adam beat Foucaulf in the February 2015 special election.
The Laborite control of the Senate achieved in late December 2016/Early January 2017, was the first left majority in the Regional seats since the June 2015 elections and first Laborite majority outright in regional seats since the February 2015 elections (Talleyrand switched to Independent during the term though).
In summary, Conservatives dominated Congress from AT-Large seats (House or At-Large Senate) from Aug 2015 until Aug 2017 and Regional Senate seats from July 2015 (three seats changed hands mid month) until December 2016, which fully encompassed Adam's Presidency.