WELL, it's officially Muster time again.

The number changing ceremony marks a milestone on the Muster journey each year and signifies the start of intensive preparations for the 35th Gympie Music Muster.

Around 50 volunteers attended the number changing ceremony today, where Mayor Mick Curran changed the 2016 to 2017 with the help of a cordless drill and a scissor lift.

Muster Chairman, Tony Nolan said the changing of the number means the action on site at the Amamoor State Forest is about to ramp up.

"At the moment we've had about 50 volunteers working behind the scenes since the start of the year. By the time Muster rolls around, we'll have, all up, more than a 1000,” he said.

The Mayor was given the honour of updating the sign atop the main stage as the Gympie Regional Council is one of the main sponsors this year.

Before the ceremony, there was a thank-you barbeque where volunteers onsite were treated to a celebratory snag before the changeover at 12.30pm.

Beneficiaries of the proceeds from the Gympie Music Muster will be Mates4Mates and diplomat and singer-songwriter Fred Smith and advocate for the charity will be just one of the dozens of acts booked to play.

Tony Nolan said partnering with Mates4Mates again made a great deal of sense.

"We wanted to help out an organisation that appeals to a great cross-section of our patrons,” he said.

The Gympie Music Muster will be held from August 24 -27 and is one of the largest out-door music festivals in the country with five separate music venues, countless bars, stalls and food vans, and entertainment that appeals to all generations.

"We're catering to everyone,” Mr Nolan said.

"From the various long-term campers to the patrons who come for the day on coaches and buses.”