Go Indy Go has regained her position at the top of Thousand Guineas markets and trainer Leon Macdonald is waiting to see if she can regain her jockey.

Chad Schofield rode the filly to her Champagne Stakes win in the autumn and committed to her spring campaign.

But the young rider's ambitions were thwarted by a month-long improper riding suspension which would keep him out of Saturday's feature Caulfield meeting.

Schofield lost his appeal before racing authorities and heads to the Victorian Civil and Administrative Tribunal on Monday in a bid to get back in the saddle.

"I told Chad I would wait until the result of the hearing," Macdonald said.

"Otherwise Steven Arnold will ride her in the Guineas."

Go Indy Go ran an inexplicable last in the Danehill Stakes at her first start since her Group One win in Sydney but bounced back for an eye-catching third in the Thousand Guineas Prelude a week ago after getting back from her wide barrier.

"We didn't find anything wrong after the Danehill and she ran terrific in the Prelude," Macdonald said.

"She has grown taller and I think she is a bit light because of that but before the Prelude her coat was starting to come through and she looked a lot better.

"She is very bright in herself and I'm a lot happier now than I was before.

"She is an extremely relaxed filly which takes her a long way."

Go Indy Go is the $4.60 TAB favourite for the Thousand Guineas (1600m) ahead of Bring Me The Maid and Lumosty at $5.50.

The Robert Smerdon-trained Lumosty won a Sale maiden on October 1 by nine lengths to convince owner Phil Sly to pay the late entry for the Thousand Guineas.

Smerdon is still not certain whether Saturday's Edward Manifold Stakes winner Fontein Ruby will join her stablemate in the Thousand Guineas.

The trainer said he would leave the decision to the owners.

"We've got until Tuesday to decide," Smerdon said.

He said if connections wanted to head to the VRC Oaks with Fontein Ruby it would probably be more suitable to wait another week and go to either the Caulfield Classic or Ethereal Stakes, both over 2000m.