Kiama's Changing Tides festival is hoping to boost the allowed capacity of the December show by 60 per cent - and also finish later.
In February this year promoter Harlow Events gained approval for a two-day music festival at Kiama Showground, with capacity capped at 5000.
The original finishing time over both nights was 9pm.
However, with the festival having pulled in names like Spacey Jane, G-Flip, Dune Rats and Peking Duk, the promoters have decided the festival needed to get bigger.
Harlow has now lodged a request to revise the original approval to increase capacity and lengthen the festival's run time.
"In February 2022, at the time of the original development application, we could have only dreamed of the success that this new event would bring to the region," the application stated.
"With the proposed calibre of artists, comes the requirement of a capacity to match their stature. For this reason, we are asking that that the capacity is increased from 5000 people to 8000 people.
"It is important to note that this amendment requires no other changes to the standing approved development application other than the increase in the people capacity.
"The need for the increased capacity is only due to the promise and opportunity that this event will bring to the area."
The proposed new end time for the festival is 10pm on both nights.
According to the application these changes will have "no fundamental change to the wider event operation".
Kiama Municipal Council is yet to make a decision on the proposal to increase capacity.
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