Perth and Kinross Council has requested additional information from event organiser DF Concerts and time will be allowed for comment on that.
An initial 28-day consultation saw more than 520 responses, split between supportive and opposing views.
A spokeswoman for DF Concerts said this was "standard" procedure and welcomed the extra time for consultation.
Perth and Kinross Council has requested information further to that contained in the original planning application "to address issues raised by the consultation".
A spokeswoman for the local authority said a further 28-day consultation period would be held to allow comments to be made on this extra material.
The first consultation drew a total of 523 public comments, 240 in support of the plan, 274 opposed to it and nine neutral.
DF Concerts has provided additional information in response to a number of comments on the application, including some which saw an objection from the Scottish Environment Protection Agency withdrawn.
A spokeswoman for the group said it was normal procedure to provide the council with an addendum rounding up key information provided since submitting the original application.
She said: "Thank you to everyone that has taken time to read the planning application and to those that submitted representations to Perth & Kinross Council.
"We have read and considered everything in full - from local resident comments to statutory consultees and additional information will be lodged next week.
"We welcome the extension of the consultation period to ensure there is further clarification in certain areas."
The initial application was submitted in January and the council said the statutory timescale for determining a major planning application was four months.
A second public consultation is to be held on the plan to host the T in the Park festival at Strathallan Castle.