The vCloud Usage Meter 3.5 is installed as a new appliance. After you install and configure the vCloud Usage Meter 3.5 appliance, you can optionally import data from vCloud Usage Meter 3.3.3 and 3.4.0 versions.
If you are upgrading in the middle of a month:
Run the existing vCloud Usage Meter appliance until the end of that month.
Use the data from the existing vCloud Usage Meter appliance for reporting for the month in which installation takes place.
Shut down and then back up the existing vCloud Usage Meter appliance.
The vCloud Air Network Program stipulates that a Service Provider needs to keep usage data for 24 months going back from the current month.