With HI policy you can set this up
Antispyware Signature File Checking
To check if a signature file is up to date, you can choose one or both options. If you select both, both conditions must be satisfied to meet the requirement.
Specify the oldest age of the signature file:
This option lets you select a relative time value of days or weeks.
Check the signature file date
This option lets you select a specific date and apply Boolean logic to the date.
If not, update the signature file
This option lets you update the signature file if it is out of date based on your settings for date. You can specify the download URL. In the execute command field, enter the following: %F%