The band have created a ten-day countdown with the backdrop "Ten" in the lead-up to their tenth anniversary. The countdown launched at 10am this morning (October 9).
The group have also launched an official Girls Aloud Twitter feed.
Girls Aloud reunited at Cheryl Cole's solo arena show at London's O2 arena earlier this week after Cole previously confirmed her bandmates' attendance.
The group have been tipped to release a new single in November to mark their anniversary and producers Xenomania confirmed in May that the girls had been laying down new material.
In August, Cole teased new Girls Aloud lyrics "I just wanna dance" during a radio interview when quizzed about their return.
Fansites have suggested that the group may record a charity single for this year's Children In Need, which takes place on November 16 on the BBC.
Girls Aloud have also been rumoured for a performance slot on Strictly Come Dancing.
"I wanna tell you everything but I really can't!" Nicola Roberts said in August of the band's comeback plans.
"It's our tenth birthday in November so we will definitely celebrating."
Girls Aloud are rumoured to be playing the 2012 Royal Variety Performance, which takes place at the Royal Albert Hall on November 19.
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