See diff of policy changes on specific gateway not updated in months prior to installing?

[basinUnaltered]

I'm working on getting our fleet of gateways in order and there are several that have not had policy pushes since early October. I'm trying to review what changes have been made to ensure that pushing the most current policy is unlikely to cause any problems by finding a diff between the policy currently installed on those specific gateways and the current policy but finding that info is proving somewhat opaque.

In SmartConsole if I visit the Security Policies section and go to installation history I can see the devices showing an Access Installation Date of October 8, 2024 but under Policy Installations History it says, "No items found." If I go to Install Policy and ensure that the affected gateways are selected the window informs me that "Changes data is not available". If instead I click on 'View Changes' I get the message, "This is the first policy installation on the Security Gateway / Cluster '<hostname'. All changes will be installed" but it is definitely not the first policy installation on that device.

It seems bizarre to me that there would be no way to compare the state of currently installed policy on a gateway compared to the most current policy prior to installing even or especially if the gateway policy is very out-of-date but I haven't found anything else in the documentation yet. Is there a method that I'm missing to be able to check this?

Gateways involved are primarily 3100 and 3200 units running Gaia R81.20, management server is virtualized also on R81.20.