A communication breakdown has given leading apprentice Anthony Allen a chance to cement his growing relationship with premier Brisbane trainer Robert Heathcote.

Allen will ride top mare Fillydelphia in the Garrards Open (1350m) at Doomben on Saturday, replacing Group One winning jockey Damian Browne.

Heathcote explained the Allen booking followed a mix-up about Browne's availability.

"I understood Damian would be riding in Melbourne on Saturday so I went ahead and booked Anthony. Then Damian decided not to ride in Melbourne but it was too late," Heathcote said.

"Anthony had already accepted the ride on Fillydelphia and he had got off Mishani Warrior who he would have normally ridden."

He said Allen's 1.5kg claim would come in handy as it reduced the mare's weight to 58.5kg.

Fillydelphia returned to form last start winning the Listed Sunshine Coast Cup (1400m) on January 26.

She is being aimed at the $100,000 Tattersall's Members Cup (1600m) on March 1.

"She is a six-year-old now and time is running out. But if she goes well in the Tattersall's race she will probably be given one more chance in the mares races in Sydney," Heathcote said.

Allen, who is now managed by former jockey Garry Legg, has been in fine form with six wins in the past two weeks.

He is one of a bumper crop of apprentices in Brisbane with junior jockeys riding six of the eight winners at Eagle Farm on Wednesday.

Meanwhile, apprentice Aidan Holt, who at one stage led the jockeys' premiership this season, will be out of action until at least next month.

Holt broke his wrist in a fall in December and hopes to get a doctor's clearance to ride next month.

Stewards are expected to resume their inquiry on Friday afternoon into the ride of NSW apprentice Rachel Murray on Youthful King at Eagle Farm last Saturday.