When netlogin and policy are used, policy will only honor vlan attributes if policy maptable response is set to both and vlanauthorization is enabled.configure policy maptable response bothconfigure policy vlanauthorization enable
That differs for each platform, you can see this in the release notes of the version you are using, in the limits section. Look for load sharing maximum number of ports.
Use UPM to act on log message vlan creation and have UPM disable igmp snooping. Below log filter is what you can use to trigger the UPM script. create log filter createVLANconfigure log filter DefaultFilter add events lldp.PktRecvconfigure log filter...
