还有一个问题

Don't care too much about that. Take that easy. Your chance of getting in at that school is slim. Sorry for my bluntness. But from what you've asked around in this forum, you are in the early stage as a beginner. Columbia is extremely selective and take few people from China mainland each year. It's quite common that seasoned applicants with stellar profile have been turned down.

As to your question, the school need to recieve your mail-in application before chaning your status to "recieved".  Simply think about that, how can you submit your undergraduate academic transcript thru online module?

Columbia很少招中国学生是过去的事实吧？去年我曾向他们索取过申请材料，他们发email来说，他们希望扩大在中国的影响力，所以特别免掉我的申请费（我可只是跟他们要了材料而已），还说学校去年开始设立了一个专门为中国出色的申请者提供的奖学金，以鼓励中国学生申请。

所以也不要太丧气，努力争取总没有损失吧？认定了失败还申请干吗！