One of the benefits of our service is that we take care of WordPress maintenance and upgrades for you. We have a standing maintenance window every Sunday from 5am to 8am, which is used to implement any necessary changes. Please note that maintenance can result in downtime to the WP editing interface and your public-facing site. This is why we schedule the upgrades on Sunday mornings when folks are less likely to be accessing and updating the sites.
We will always notify our customers of any changes that are scheduled via our mailing list.
DoIT will always post known outages on their Outage page here: http://outages.doit.wisc.edu/