1. Is I-539 form e-filing better than paper option? For example, it looks that if using I-539 e-filing, we can get the receipt instantly;
>> Yes, e-filing is better. You got the point - that way you can make sure T1<T2, as I answered your previous post.
2. Do we really need to attach original I-94, or copy of I-94 is fine?
>> Is the original I-94 that important to you? My suggestion is it's always right doing what USCIS asks you to do. Keeping a copy of I-94 is more than enough for yourself.
Thanks.
>> Sure.