When new info is added to the banner, if you have a chat open with the banner, the info will not be updated there. Only if you refresh the page.
Let's take springtime as example. It didn't have a countdown at the time X, someone opened a chat with the banner and it didn't show one (as expected). A few minutes later, the countdown is added to the banner. The banner of the chat previously opened won't show a countdown until the page is refreshed. I'm not sure if that's how it's supposed to be or if it should be updated without having to refresh the page.