obviously off-topic, but could you please clarify (and may be post some links?). Does this means, that if I now cancel my greencard and leave usa back to my home country, up to 2022 usa irs will have some rights on my income?
http://www.taxesforexpats.com/expat-tax-advice/citizenship-s...
If you move back to say Australia there are still negative tax consequences in so far as some Australian tax strategies that are quite beneficial will have those benefits negated when the US tax system is brought into account.
This will vary from individual to individual so seek a professional tax agents advise for your situation.