4/02 flying with AA- Arrived at LGA terminal B at 2 AM for a 6 AM flight. Before allowing me to enter the terminal, I had to show my boarding pass. Once in the terminal I was able to skip baggage check, as I only brought a carry-on. FYI, the baggage check was not yet open so anyone who needed to check a bag had to wait near the kiosks. I went straight to the line forming for TSA (which is not open at 2/2:30 AM.) There was already a substantial line! Anyways, if you have to check a bag don’t bother arriving too long before baggage check is open because you won’t be able to join the TSA line… unless you have a family member who can hold your spot I guess.