Spikes of APNS unavailability

We randomly get spikes where we cannot connect to the APNS server. Has anyone encountered this before? Is there behavior that will cause APNS to start terminating our connections or to start rejecting our connections? We did not see any 429s during this time.

Sample errors:

Exception- System.Net.Http.HttpRequestException: An error occurred while sending the request. ---> System.Net.Http.WinHttpException: Error 12029 calling WINHTTP_CALLBACK_STATUS_REQUEST_ERROR, 'A connection with the server could not be established'. Exception- System.Net.Http.HttpRequestException: An error occurred while sending the request. ---> System.Net.Http.WinHttpException: Error 12030 calling WINHTTP_CALLBACK_STATUS_REQUEST_ERROR, 'The connection with the server was terminated abnormally'.

Spikes of APNS unavailability
 
 
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