Extended VDOM license and license expire

Does the extended VDOM license have an expiry date? I can not seem to find any info on this. I have a cluster with v5.6.6 that we are phasing out but we need it to live a couple of months after the FortiGuard license runs out. I'm aware that after license runs out we need to remove the web security profile from rules in order for web traffic to work, but besides that the FortiGate will still function as a normal firewall.