ABC will formally announce the full line-up on Friday (July 27), but sources have told Entertainment Weekly that season ten's Anderson and the eighth season's Rycroft are both expected to return.
Joey Fatone, who placed second in 2007, has also been tipped for a spot in Dancing with the Stars: All-Stars.
A production insider has suggested that producers are planning an interactive element for the show's fall return, with three former contestants competing in a public vote to earn the show's final slot.
Carson Kressley of Queer Eye is expected to be among those up for the public vote, although it is not yet clear who the other two celebrities will be.
ABC declined to comment on the casting rumours.
Misty May-Treanor has openly campaigned to join Dancing with the Stars: All-Stars in the past, with Kate Gosselin linked to the series as well.
Earlier this week, season nine's Melissa Joan Hart said that she is not interested in competing on Dancing with the Stars again.