So ... we find ourselves with the issue reported Aug 27th ... it is now November ... there are over 180 postings and north of 23K views just on this thread alone ... hmmm ... you would think getting iCloud for Windows to work with Office 365 / Outlook 2016 might, just might get the attention of Apple. I see brave souls on this thread wading into the telephone support labyrinth pleading the case. Just looking at the numbers of threads on this topic and views, you could arguably state that this is a fraction of the users experiencing problems. Often times people just give up and choose different technologies.
The only "solution" to date is to roll back to Outlook 2013 which for a time worked, until v5 of iCloud was released.
I have found Apple Support Communities to be a fantastic source of troubleshooting and finding answers. Seldom if ever have I seen such a major, visible issue, impacting tens if not hundreds of thousands of users go unaddressed by the company so many of us have admired for years. Apple, I sincerely am rooting for you and hope this gets resolved quickly. The longer the delay, the higher the likelihood of losing future customers for phones, tablets, and laptops which would be a shame. Please, while there is still time, deliver a robust fix for inter-operability with Outlook 2016 and iCloud for mail, calendar and contacts.