A lot of people who downwind paddle on the Gold Coast leave from Kingscliff these days. Kingscliff to Hastings or Pottsville in Northerlies and Kingscliff to Snapper in Southerlies. The wind is always a good 5 knots stronger south of the border.
Get on Facebook and have a look at Gold Coast SUP Racers or Roar Industries Paddle Group. People are often posting planned downwind runs a day or two ahead.