Thread:Talk:Echo (Notifications)/Mentions require signature with timestamp?

I've been testing this out on our corporate wiki (currently MW 1.23.2). It seems like for a mention to work, it has to include the wiki-link to the user page I'm mentioning followed by a wiki link to my user page AND a timestamp. Is that correct? I'm curious if it would be possible to make use of the functions that determine who made an edit and when (like what is used for the Recent Changes page) instead of relying on a signature. In my tests, even if I use both usernames in links (the "to" and "from"), but don't include a timestamp, it seems to not be recognized by Echo as a mention event.