Hello Paul, I am Keith, one of the experts on Just Answer, and happy to help you with your question. Firstly there is no such Department as the Inland Revenue. It was merged with HM Customs and Excise some years ago to form Her Majesty's Revenue and Customs (HMRC).
There is a Double taxation Treaty between the UK and Oz which precludes the same income stream being taxed in both jurisdictions. This is achieved by means of tax credits, the tax paid in one country being allowed as a tax credit against the liability in the other. The Treaty does not, however, protect the individual from differences in tax rates.
I can understand your problem as Australian Income Tax for non residents is at 32.5%.
At present you are stuck between the proverbial rock and the hard place. I suggest that you contact the Australian Taxation Office with a view to resolving the situation. However, I suspect that like all revenue offices the world over, their view on life tends towards the jaundiced. Normally one would expect an UK resident not to have to bother with other jurisdictions' taxation systems, but this is not always the case. I have an old work colleague who now lives in France where his UK injcome, all derived from UK Governmnet pension schemes, is tax free in France, but his State Pension is taxed under French taxation. Thus he has to make returns in two countries, so you are not alone.
I submit that your solution at thuis stage is to get the Australian Taxation Office to agree that you no longer need to make returns in Oz.
I do hope that I have been able to show you a way forward in this matter which may ease your present administrative inconviences.