Even though disabling Dir Sync is not daily task for Office 365 admins, you should know how to do that if you need to do that. In older versions of Office 365 Admin Center, disabling Dir Sync was one of option from UI, but option is removed a long time ago. Process is still pretty simple, but need PowerShell interaction 🙂
Once you connected to you Office 365 tenant, you can check status with command
Status can be changed with command
Set-MsolDirSyncEnabled –EnableDirSync $False or Set-MsolDirSyncEnabled –EnableDirSync $True
First changing of status will be visible (in most cases) in next 5-10 minutes, but if you want to change status again in short time, you need to wait up to 72 hours, but in most cases you can do that in next 12-24 hours.