Pretty sure I'm actually hosted on O365, but I don't think it's relevant. Sunrise doesn't even see the account when I try to add an Exchange calendar. It pops up a message saying something like "There is no Exchange accounts [sic] on this phone". This seems potentially related to the fact that the Gmail app is now handling Exchange accounts instead of the default Mail app.
Here are a couple of reviews that mention this issue:
Here are a couple of reviews that mention this issue:
https://play.google.com/store/apps/details?id=am.sunrise.and...
https://play.google.com/store/apps/details?id=am.sunrise.and...