In general, I'm not sure if I understand completely what you did, what happened and what you noticed on 2023-09-12 and 2023-09-13, especially at which time. If you can reproduce the issue without using a static IP address, I'd suggest the following test:
Configure the guest OS to use DHCP and shut it down. Start taking notes of possibly relevant events with your local time added during the following: Start the VM, reproduce the issue and shut down the VM from within the guest OS. Provide a zip file with the contents of the VirtualBox global configuration folder (contains the DHCP related information amongst others) and another one with the VBox.log file and your notes. I need this double time keeping to see if your (perceived) times and VirtualBox's (measured) times match, because both could potentially be flawed (no mistrust intended
