Just wanted to clarify this policy.

CrashPlan requires a device to connect to it's backup at least once within a 6 month period. This is to ensure the integrity of the data we're storing. Part of CrashPlan’s ability to maintain the backup health and integrity relies upon regular connection from the device. CrashPlan is able to routinely perform maintenance on the backup by comparing checksums between both device and CrashPlan Central. If you are unable to connect the device to the backup within a 6 month period, you can also perform a restore from the backup as this qualifies as recent backup activity.