Robbo77,
Best time to catch barra at Monduran, is when your at the dam.
Lots of threads on this issue, do a quick search on Moon phases Barra, and you will find heaps of information.
Have a good read of comments of people like Jas (the_matrix) and Johnny Mitchell (A_Diff_Perspective). They certainly have a lot more quality water time fishing for these fish than most of us just dream about.
Will be up there myself around this time, and so will be alot of other Ausfishers.
All will be glad to give you all the help you need.
Remember the dam is very large and lots of timber and big fish. My favourite dam of all the barra impoundments that I have fished.
Regards
Trev
P.S.
PM sent