DeviceActivity monitoring limits

Within the DeviceActivity API, the documentation for DeviceActivityCenter.startMonitoring says: "Attempting to monitor too many activities or activities that are too tightly scheduled can cause this method to throw an error."

Is there a documented limit of the amount of activities that are able to be monitored simultaneously? I understand that monitoring "too many activities" will throw an excessiveActivities error, but I can not find documentation that specifically identifies the conditions that this error can be thrown.

The documentation you linked seems to say that the limit is 20:

The maximum number of activities that can be monitored at one time by an app and its extensions is twenty.
DeviceActivity monitoring limits
 
 
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