Bryan Cooper has been installed the 5-1 second favourite to win the Irish jockeys' title amid reports Davy Russell has been deposed as No.1 jockey jockey for Gigginstown House Stud.
Cooper has often stepped in for Michael O'Leary's owning and breeding operation and is behind only 1-8 chance Ruby Walsh with Paddy Power while defending champion Russell is a 14-1 shot.
Russell has claimed many major victories in the maroon and white Gigginstown colours, winning the 2013 Hennessy and Punchestown Gold Cup on Sir Des Champs and at the Cheltenham Festival aboard the likes of Weapon's Amnesty, First Lieutenant and Carlito Brigante.
Neither Russell nor Eddie O'Leary, Michael's brother and Gigginstown manager, could be contacted by Press Association Sport on Tuesday.
Russell won aboard the Gigginstown-owned Rogue Angel at Punchestown during the afternoon, and is booked for the mount on Roi Du Mee in the Holden Plant Rentals Chase at Tramore on Wednesday, along with two other Gigginstown-owned runners.
Russell's most recent Grade One success for Gigginstown came on the Gordon Elliott-trained Don Cossack in the Drinmore Chase at Fairyhouse at the beginning of December.
He rode his 1,000th winner over jumps on Sea Light for long-time supporter Charles Byrnes at Leopardstown last week.