看過皮匠老師的文章建議在B2六個月快到期時申請。很不幸他們這次入境時隻拿到三個月居留。理由是這次在國內呆的時間比上次在美國呆的時間短（其實隻短幾天）。
以下哪一個才是最佳選擇？
1.三個月到期前即遞申請 - 會不會因時間太短有什麽風險？
2.先申請延期，再申請移民 - 可萬一延期被拒或者又隻給三個月呢？
3.到期先回國。走境外申請路線，或
4.到期先回國。過一段時間再來，然後再申請。
3和4可能保險點。可是太折騰耗時了。
-Your parents may just overystay (illegally stay) in US for a one or two months and then, you file I-130 and they file I-485 together. Their illegal stay does not affect their green card application. They had better stay home (not travel) before they file I-485 in case some uncertain situation occurs (e.g. something get police involved).
