Regarding the upgrade... you'd need a service contract to download software but thanks to KRACK Extreme Networks offers a one time download to for the fix even if you don't have a contract........
https://extremeportal.force.com/ExtrArticleDetail?n=000018005
Extreme Networks will be offering a free, one-time download for ExtremeWireless and ExtremeWireless WiNG customers that are without a paid maintenance contract.
This one-time download will provide access to an updated firmware release, but will not include additional warranty or support from Extreme Networks without a paid support contract.
The firmware will be available on currently supported access point and controller models only.
This one-time download will be available soon, and the link will be provided on this page when it becomes available.