Preheat oven to 325F. Grease & line base & side of a 9-inch springform pan with parchment paper.
Combine butter, syrup & sugar in a medium saucepan over medium heat. Stir until butter is melted & sugar is dissolved. Remove from heat & let cool for 5 minutes.
Add oats & flour & stir until well combine. Using a flat bottom & straight-sided glass, press mixture over base & about 1 1/2 inches up side of pan. Set aside on a baking sheet.
Beat the cream cheese, sugar & vanilla together in a large bowl using an electric mixer for about 3 minutes or until sugar is dissolved & mixture is lighter in texture; scrape down the side of bowl. Add the eggs one at a time, scraping the side of the bowl down with a spatula after each addition. Beat until eggs are combined - 1 to 2 minutes. Do not over beat (over beating can cause the cheesecake to crack). Pour filling into the crust. Bake, on the baking sheet, in the center of the oven for about 40 minutes or until almost set. Turn oven off & allow to cool for 2 hours in the oven. Remove from the oven, cover loosely & cool for 1 hour. Cover & chill for 8 hours or overnight.
To make the Golden Syrup Caramel: Combine all ingredients in a small saucepan. Stir over medium heat until the butter is melted & sugar is dissolved. Bring to a simmer & simmer for 2 minutes. Remove from heat & let cool. Store in a seal container for 8 hours or overnight.
Just before serving: remove the cheesecake from the fridge, loosen ring & either serve on the springform base or run a large knife underneath the cheesecake & place it on a serving plate. Warm the topping for about 20 seconds in the microwave until runny but still thick - don't overheat it. Drizzle all over cheesecake & cut into wedges to serve.