It has resulted in the entire April 14 concert at North Wollongong to be cancelled, along with other dates in Coolangatta, Geelong and Perth.

"This is due to John's recent illness from which he is still recovering," Zaccaria Concerts and Touring said in a statement. "We wish John all the very best for a speedy recovery."

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Farnham was the main event for the event though music heavyweights were also to hit the stage: Daryl Braithwaite, Jon Stevens, Vanessa Amorosi, The Black Sorrows and Ross Wilson.

Refunds will be given through Ticketmast either online, on the phone of in person at an outlet. Patrons are advised to contact Ticketmaster by March 14.

However, all Red Hot Summer Tour dates will go still ahead as planned with the first show being March 23 at Batemans Bay.

On the RHST Facebook page, organisers stated Farnham's workload had been "impacted and reduced" and confirmed the star would still perform.

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