Can I upload IDOC documents 2 times?

Some colleges are requiring 3 documents from me. Parents’ Tax returns, Student’s Tax returns, and business supplement. I have both tax returns ready, but not the business supplement. Am I able to upload the tax returns now and after submit the business supplement? Or I need to upload everything at once?

Yes, just label them separately, you may get an email from a school who for some reason isn’t accessing it like I did but you can always offer to scan and email directly.