Yeah I mean they... really aren't needed. You can just have the chara tagging again and be like, oh yeah I returned yesterday! 'sup. If we usually have certain "types" of posts, like the returning ones or the bawww-someone-left ones it's mostly because we're used to those, I think.
If anything, this'd actually encourage less of the standard, generic-ish posts like that so it seems like it'd be a good thing all around.