A new month means a new start for one K-pop girl group.

SM Entertainment revealed on Tuesday that its group f(x) has begun preparations for its first release since the departure of former member Sulli (Choi Jin Ri) earlier this summer. The revamped group will begin filming a music video on September 11.

The exact date of f(x)'s return to the K-pop scene as a quartet has yet to be be determined, reports the K-Pop Herald.

SM Entertainment revealed that f(x) will promote a new album by the end of the year.

f(x)'s comeback announcement comes over a year after the group released their last album, "Red Light," in July 2014.

The group's promotions of "Red Light" were cut short last year due to Sulli's hiatus following malicious rumors relating to her relationship with Dynamic Duo's Choiza. The two have since confirmed they are dating.

f(x)'s upcoming new album also brings the return of leader Victoria from China, where she was engaged in solo activities. She will join f(x)'s other members- Krystal, Amber, and Luna- in preparations prior to filming the music video.

After f(x)'s members focused on solo promotions and went without Sulli for several months, SM Entertainment announced in August that Sulli would officially leave the girl group but continue to be managed by the entertainment powerhouse as she pursued an acting career.

The group performed for the first time as a quartet in London last month.

f(x) debuted in South Korea in 2009 with the song "La Cha Ta." They are known for their experimental fashion and electropop sound.

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