Hi Ian Cowan. I hear your frustration. The service is not a spigget we turn on full blast out of the gate. That method that does cause issue at scale. And the roll out plan for communication sites follows a fairly established plan that has proven well for the SharePoint workloads across the last two years, with the balance of many customers asking for more control and communication about adjustments to the service. And know that each service within Office 365 releases a little differently per the needs of the services itself, variance of app vs Web, and the methodology of each engineering team based on where and how they roll out, update v. new, et al.
All that said, let me loop in Andy Haon who might have some thoughts, and you can preemptively review what he shared about the roll out plan all up during the SharePoint communication sites AMA: https://twitter.com/sharepoint/status/880122709312544769.
If you are First Release "Select users" - you will have the capability soon, well ahead of your Sept. 1st deadline. And to your advantage, they truly are fast and easy to set up.
Hang in there, and thanks for hanging in there,
Mark