That's the space status update message that two people upstairs said. When the landlord just updates the blog, there will be a new message in the space that XXX has published the blog, but when your friends update a lot, yours will also be refreshed, but that doesn't matter. What you want is to display log updates in the signature file.
There is another way, if you want others to find out that you have updated your blog, you can modify it every once in a while, so that someone will modify the space news, but friends can always see it in space, hahaha.