When I applied years ago, I never had any LORs. They told me to bring them to the interview though. A buddy recently applied. No LORs. Got a video interview. So, I’m sure they will be looked at when they need to be…and it appears they don’t necessarily help to get an initial interview. But that’s just two anecdotal datapoints. I don’t really know. But to answer your question, I would guess if you add it after the fact, it’s still attached to you and your app in some way and can be seen when it needs to be.