SonicOS 6.5.4.6 release enhances SD-WAN to support scalable tunnel interfaces for distributed enterprises. This increases the supported number of remote sites from 100 in previous versions to up to 1000 sites in SonicOS 6.5.4.6.
Configuration maximums are increased for a number of SD-WAN settings.
SD-WAN Maximums per Platform:

NOTE: Please refer to KB How Can I Upgrade SonicOS Firmware? for upgrading to the latest version to see these enhancements.