Comment 7 for bug 1540461

I found out what's causing this issue.
Actually it's a bug in MS Exchange 2016.

Thankfully the evolution-ews developers created a workaround to solve this issue.
See here for further details:
https://bugzilla.gnome.org/show_bug.cgi?id=771370

The recurring events are not displayed correctly if one of the instances is detached, i.e., is moved to another day.

You need to recompile the source yourself, including the patch or wait for the next release.