This is the banner I'm talking about:
Note the last part of the text. It's a time. Usually for first-time suspensions, the time reads "in 23 hours" or "in 7 days", which does not give any exact timing when hovered over.
This is also useful as in the hundreds digit is not shown, and it may be relevant in some cases. For instance it caused confusion here as a user was listed as suspended until '18, when it actually ends in 2118. This is where the hover text can be helpful as to clarify that it isn't 2018.
All "time"s I can find on SE have this feature, for example:
Should this be added for the suspension banner?