Written by Thomas Speekenbrink
When you use Office 365 with a lot of users it could be that you experience throttling issues from time to time. More info.
In Office 365 you cannot edit the Throttling policy. So what to do?
Our advise is to devide the users in different ranks. For each rank you should have a different SyncUser in place. This way you can devide the load to different SyncUsers and minimize throttling. Based on our best practises, we have learned that deviding the users into ranks of 50 users per rank is the best option.
How to setup the Exchange Online Synchronizer with ranks is described in this article.