Manifest with Elite Names, Status and a "Y"

Hi all,
I was curious about something when I saw the manifest in the galley. I quickly glanced at it when I had to excuse myself to the lavatory. I know, shame on me, the paperwork are not for my eyes to see but I simply did a 5 second glance. I was in F with other PMs and DMs. 2 of us including myself had a "Y" after our names. Could this be a notation of some sort? It can't be Y for economy as all my legs were in F. I'm not a MM nor do I send out too many complaints lol. Just a little curiosity.

Thanks everyone!