I read your quote
During pendency of I-140/485
由于有了移民倾向，你的单纯的非移民签证 (F/J/B etc) 会是你回美的障碍，除非你怀揣 AP.
对于 H/L 而言，若前次入境用的是 AP，则不适用＂30 天＂。必须继续使用 AP 或使用有效签证。使用了 EAD 与否无关紧要。
me and my son both 485 pending, my son used AP came back last time, and I used H1B visa came back.
1. so, I can use H1B status come back to U.S. after landing Canada, right?
2. accoring to your quote, I think my son need use AP come back US from landing canada. should he use AP's I-94 card or should he use the AP paper which stamped when last time he came back? or he can try H4 first, if does not work, then use AP? which way is better?
3.if by any chance, you know the answer of the following question, could you help me too?
since I am going to landing canada on this Sat. So I can not apply SIN, Is it possible I can apply it later when I reenter canada, maybe one or two years later?
Is there any $ limit for 'import to canada tax free'?
thank you very much!