This question is best asked by presenting the following scenario:
I own an manage an HCP appliance in my data center.
On January 5th, 2018, I write file filename.txt to a compliance namespaces on HCP and set its retention to 1 year.
On January 6th, 2018, I change the system time on my HCP appliance to January 6th, 2019.
Is there anything stopping me from deleting filename.txt?