Office 365 Message Center Notifications - Expiry Date?

[Vinod_Bhargavan]

Is there an expiry date for a notification/message that shows up in the Office 365 Message Center? 

How long are the active messages shown for and how long are the dismissed messages shown for?

[#2]

To my knowlege, I'm not sure if this information is available somewhere, but this article is worth to read about how the messages in the message center work: https://docs.microsoft.com/en-us/office365/admin/manage/manage-messages?view=o365-worldwide