Is there a way to check in online using saved reservations WITHOUT having your confirmation number? American allows you to log in using your AAdvantage number, then check in for existing reservations if it's within the allowable time window, but I can't find any way to check in without the confirmation number on Southwest.

On Southwest.com, I can see my existing reservations after logging in to RR, but when I select "Online Checkin" under an existing reservation, it asks for my confirmation number.

I hate having to keep track of the itinerary - what I've been doing is emailing another copy of the itinerary to my home email address, then when I check in, I go into my email and copy the conf. # from there. Just wondering if there's a better "paperless" way?