Ann: FY17 Half Year Investor Presentation, page-23

I think it might be people getting in this week before others get in later before it goes ex div to get the dividend - the question will be if they then sell after ex-div date early next week, if you can do that without losing any capital then its a reasonable good div return for a short period...the volume is certainly higher than average, so I wouldn't be surprised if people are doing that.

At $1.20 that's a 3% fully franked dividend return for less than two weeks of cash out the door (assuming you sell out at buy price excluding brokerage after ex div date) - better than having it in the bank for the same period just have to watch that the price doesn't drop 5c or more after ex div date and your ahead.