I'm a US citizen living overseas.
1) If I file an extension, do I get an extra 6 months for all forms (e.g. schedule B?) or are there certain forms that the extension does not apply to?
2) In Sept. 2015, I will have been out of the US long enough to meet the physical presence test. This will excuse me from from a penalty for not having health insurance in 2015?
3) Suppose I file in Oct. 2015 (but pay in April 2015, as required) and don't use FEIE or FTC because I believe that I will not owe taxes in my resident country. Later I learn that I was supposed to pay taxes here. I will have until April 2018 to amend my return and claim FEIE and/or FTC and avoid having paid double income tax?
I talked to several local accountants in my resident country (it's a developing country) and they all didn't really know whether I would need to pay taxes given I am self-employed and make all my income online and also don't deposit any of it into my bank account in my resident country...but the general consensus was that I won't be responsible for any taxes. SO, I just plan on paying tax to the US and regard it as my tax domicile. I'm just concerned that in 2 years or so I might get a tax bill.

