Nightspore,ADR or American Depository Reciepts are managed by...

Nightspore,
ADR or American Depository Reciepts are managed by the Amirican counterpart, in this case Bank of New York. They have bought DIO shares, bundled them up and offer them out as ADR's.
The issue you have is with BoNY. I would suggest that if you have not sold them then you will own the unbundled version, ie Australian shares, but with the BoNY as the registered address.

As a thought, this might be a reason why the stock has been so weak over the last 2 mths. If the BoNY is unbundling the ADR's they may also have been selling them down in the Australain market, hence the weird lots of 300 and 500 share sales. If that IS the case, then you will have a cheque coming to you in USD, I presume....

PS I'm only guessing about the last bit...