S2 Q&A: Do I upload all my previous I-20s or just the current one?

The current one (with the OPT recommendation page if you're on OPT) plus any earlier I-20s you have - schools use them to see your full F-1 history and CPT/OPT usage. Missing an old one? Upload what you have and say so; your SEVIS record carries the history. Do you have the current I-20 as a PDF?