Managed device attesation fresh certificate expectancy duration

When a DeviceInformation command along with ManagedAttestion data in the query along with a new nonce and after 7 days last time we queried for fresh certificate, is there a possibility that a) we will get a DeviceInformation response without a Managed attestion certificte. OR b) We will get a cached certificate
Also, what's the average increase in expected response time when we query Managed attestation certificate in DeviceInformation.

Managed device attesation fresh certificate expectancy duration
 
 
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