SEP Upgrade - keep definitons

Hi guys,

we want to upgrade our clients to from SEP 11.x, 12.1.x to 12.1.5 by using our SCCM infrastructure. As far as I´ve seen the AV and NTP definitions are extracted from the install package. Is there a way to keep the definitions from the installed SEP client? The SEP client has the most current definitions before the new version is taking over after the reboot. This also reduces the package size dramaticly from ~400 MB to ~80 MB.

Thanks for any hints...