Foreign National and tax provisions

[sujittalukder]

An Indian hospital wants to engage an Australian doctor for surgical works and consultancy services. For this, the Australian national will require to come in and stay India for which the Indian Hospital will make payment to him. He stays in UK and the payment will be required to be remitted to UK.
In this process, he may be required to stay in India during a previous year:
a)   more than 182 days or;
b)   less than 182 days

Under situation a); where he stays for more than 182 days in India he will become a "resident" in India under the Income Tax Act and the provisions applicable to a resident, will apply to him. In this case, DTAA with Australia or UK will not apply and the provisions of the Act will only apply. Also TDS will be made u/s 194J @ 10%, if PAN is available or 20% if no PAN is available.
Also, his other income which accrued or arises outside India will also be taxed in India for that relevant previous year.
Suppose, he stays in India for 200 days in previous year 2012-13 and remaining 100 plus days in UK or Australia then his Indian income as well as world income will be taxed in India for the FY 2012-13. He may get credit for taxes paid in Australia or UK as per DTAA in India.

Under situation b), DTAA with UK or Australia will come into play. Article 14 of DTAA with Australia and Article 15 of DTAA with UK contains the provisions related to 'Independent personal services'. Under Australia DTAA, income from fixed base in India will be taxed in India and withholding rate of tax will apply to such income. Another condition is that if he stays in India for more than 183 days then also such income will be subject to TDS in India. Under DTAA with UK, the former condition is similar whereas in the later condition, 183 days is replaced with 90 days. His other world income will not be subject to tax in India.

Is my understanding for both the situations correct; especially under situation a) where he will be liable for world wide income in India and that he will get credit  for taxes paid outside India?

Members may throw light on new angles which I have missed.
Thanks and regards
Sujit Talukder