With the 500-1000 demonetisation what becomes the status of the Indian currency held abroad? Nepal, and Bhutan officially use it, and recently Zimbabwe had added the Indian rupee to their list of currencies. Also other countries that have Indian currencies with them will be Maldives and Mauritius. Not to speak of the Indian currency held by Indian nationals, Indians of other citizenship, and foreigners who come to India often who will not be coming before 31st March next year to India.
Compared to the last Morarjee Desai domon of high denom currencies this time the Indian currency is visible in other countries. When I visited Europe in 1990 I found none of the money changers exchanged Indian currency. I don't know of Europe now, but the countries mentioned above surely do.
And money changers in many countries accept Indian rupee. I have seen counters with our country flag at money counters in the Gulf, HK and Singapore. Others on my friend list who are better travelled will know other places.
So there will be a tonne of Indian currency lying in various such countries officially and unofficially. Is that all vaporised? It is not black money. You can officially take ₹25,000/- abroad and convert it to local currency wherever they are accepted like the countries I have mentioned.
At the time it puzzled me as to what these chaps do with the Indian currency in their possession. After all international trade is no in our currency. I used to wonder where the Indian rupee held by a money changer in that country would head to. Does he send it to his local bank. Now boom all those notes however little held in demonetised denominations are gone.