Due to unforeseen complications with this release, it was rolled back on 9/21 as communicated via the iModules status page incident. http://status.
On July 31, 2017 the release of caching improvements caused a degradation in performance and was promptly reversed. Since then, we've identified and resolved the issue with Site ID caching that caused the negative impact on performance. With the September 20 release, we will re-activate the caching improvements attempted in July.