Question: When did singing sisters Cimorelli post their Youtube cover of Payphone?
About the article "Payphone (song)", section "Covers".

Candidate passages:
Cimorelli (sim-or-ELL-ee) is a singing group popularized on YouTube and signed to Universal Music's Island label.
Cimorelli is made up of six sisters, Christina, Katherine, Lisa, Amy, Lauren, and Dani.
Their singing style is mostly using a capella with occasional instruments.
They started posting covers of songs on YouTube, before releasing original songs.
, the group has released four Extended Plays (EPs). 
On 7 May 2012, singing sisters Cimorelli posted a cover on YouTube, which has been watched over 15 million times but Dani and Lauren changed up the rap.
Tanner Patrick, Dave Days, Megan Nicole, Tiffany Alvord and Avery also posted cover versions of "Payphone".
In July 2012, Canadian indie group Walk off the Earth released a cover on YouTube where many of the instruments being played are looped live, allowing one member to effectively play six instruments over the course of the song, with the recorded loops all playing at once.
The same month, the band Boyce Avenue also released a cover of the song.
American post-hardcore group Crown The Empire has done a heavy cover of the song as well for Fearless Records' compilation album "Punk Goes Pop 5".
Comedy rapper Rucka Rucka Ali recorded a parody, "Dago", on his 2012 album "Rucka's World".
In October 2012, Daniel Evans, a finalist on season 5 of The X Factor (UK) published and subsequently released an acoustic piano ballad version on his YouTube channel.
Amy was part of the first YouTube video Cimorelli posted, a cover of Miley Cyrus's Party in the USA.
The band has also posted many other covers.
She sings in the alto vocal range.
Amy also plays rhythm guitar in many of the band's a capella YouTube videos as well as in concerts.
The band is currently working on their debut album. 
Career.2007-2008: Formation.
In 2007, the oldest five girls of the family launched Cimorelli as a vocal group.
They recorded covers of charting songs and uploaded them to YouTube every few weeks.
In 2008, the girls released their first EP.
Each song was written by Christina and Lauren with the vocal harmonies arranged by Lisa.
It has not been released under a record label, but it consists of the following songs:  "Singing My Song"  "On the Radio"  "Delaney"  "Hello There"  "Everything Has Changed"  "Do You Know"  
In 2012, the song was also covered by metalcore band Issues on "Punk Goes Pop 5".
In May of 2012, Cimorelli covered this song for a contest called "The Bieber-off" and Cimorelli won the contest after May 21st, 2012.
In 2012, actor Jaden Smith, who is also a friend of Bieber, has made a remix to the song entitled "Flame (Just Cuz)".
Another remix featuring Mac Miller, Asher Roth and 2 Chainz was released on May 24, 2012.
On April 18, 2012, Marina and the Diamonds covered the song during a performance at BBC Radio 1's Live Lounge.
During the performance, she changed the lyrics of the song and according to Jeff Benjamin of "Billboard" magazine, "have put a completely different spin on his track, turning The Bieb's latest into a dark, acoustic lament".
In 2012, Kevin McHale and Darren Criss (as their characters Artie Abrams and Blaine Anderson) performed the song in a mash-up with Britney Spears' song "Boys" in episode "Britney 2.0" of musical TV series "Glee".
The rapping duo Ying Yang Twins remixed "Boyfriend" on the week of May 10, 2012.
D-Roc, one of the members, explained that after his friends compared Bieber's song to their song "Wait (The Whisper Song)" (2005), "I was so amped up to hear the song too.
When I actually did, I listened to it and I was like, it sounded like us.
He complimented us," he said.
"So I wanted to compliment him by getting on it."
A mashup of "Boyfriend" and 'N Sync's 2002 single "Girlfriend" was uploaded on YouTube by mashup artist Raheem on July 13, 2012 and quickly became a viral video.