Premier trainer Robert Heathcote has altered plans for star galloper Buffering in the lead-up to the Sydney autumn carnival.

Heathcote had originally planned to run Buffering in a barrier trial on February 25 but has brought his initial autumn hit-out forward to Thursday.

"They are going to let us have jump-outs on the course proper at Doomben on Thursday," Heathcote said.

"Buffering is flying and I would rather he had a solid workout on the course proper than the A grass.

"I will probably give him another jump-out in a fortnight after that."

Buffering will then head to Sydney where he will tackle the Challenge Stakes (1000m) on March 15 at Randwick.

"I understand Zoustar will be running in the Canterbury Stakes on the same day. So we won't meet him until the Group One T J Smith (on April 12)," Heathcote said.

Buffering, who has won three Group Ones this season, can make a real challenge for Australian horse of the year if he takes out the T J Smith, according to Heathcote.