On April 2, 2018, we simplified the Application Insights pricing plans. For the Basic plan, we removed the cost to use Continuous Export and enabled the Application Insights connector to OMS Log Analytics. As a result, the Enterprise plan will no longer be available to many subscriptions which are not in an Enterprise Agreement as it no longer offers any advantage to customers.
A result of this change is that, effective at 04/02 13:00 UTC, Application Insights created from an ARM template with the "Application Insights Enterprise" are receiving a 400 return code. However, in order to allow customers to have additional time to respond to this breaking change, we will temporarily silently convert Application Insights resources from "Application Insights Enterprise" to "Basic" until we have time to communicate this breaking change to affected customers.
To remedy this, you need to change CurrentBillingFeatures to be "Basic" instead of "Application Insights Enterprise". We apologize for any inconvenience.