Following up on my first post while sorting her re-registration packet. I came across a page on what to do when USCIS later asks for proof of what you submitted: https://www.o1eb1.com/en/rfe-request-for-evidence
For those who re-registered this cycle: do people just keep the tracking page and receipt notice somewhere safe, or a full copy set of the packet too, in case you have to show it later?
