ISSUE
When using the “Wait for Event in List Item” action within a Site Workflow, if the item is updated with the Updated Item action the "Wait for Event" action never progresses. RESOLUTION
Use the Office 365 Update Items action instead of the out of the box Update Item action.ADDITIONAL INFORMATION
The Update Item action does not trigger the item updated event receiver, which prevents events such as workflows starting on item update or the "Wait for Event" action from triggering.