Silverware ID mark help

So after my dad passed recently I was looking through the silverware that was in a very delapitated anti-tarnish package. According to some research it’s the ON146 or Debutante/princess. I wanted to perhaps gather the rest and complete the whole collection since I think my mum(messy divorce) perhaps pawned parts of the collection. However in pieces I’m finding the backs don’t match mine. So I wondered if someone could help me out in figuring out why mine doesn’t match others. It doesn’t have AA Heavy on back just the names. Please see pics.