When I logon to my account to check balance, I realised I got 7gb instead of 6gb from previous BOGOF deal, then I checked Kogan website and noticed that both the 2gb and 6gb have been given another 1gb extra data, and you still get a discount on this 365 days plan purchase till 30th June, so sweet!
2GB is now 3GB
6GB is now 7GB
Unchanged for 16GB and 23GB
Note: Thanks for Mods who helped to update my title to include data details and prices, this is my 2nd deal post ever since 2009 (Thx Mossy for pointing this out) and I am touched with such a flooded responses, thanks all!