If you factory defaulted your R600 running Unleashed, look for open auth WLAN called Configure.Me-XXYYZZ (with the AP's last 6 MAC characters), to get to the AP.
You might also access it by IP if you have access to the DHCP lease server to look for the AP MAC.
The default page for an Unleashed AP asks What would you like to do?
- Create New Unleashed Network, - Join Ruckus Cloud as a Cloud manged AP, or - Show AP Info.
Click the Show AP Info, for the IP, model, SN, and version, as well as an Upgrade button.
Click the Upgrade button, and point to a 100.x base image for R600 that you save Locally on your PC,
available on Support at this link:
https://support.ruckuswireless.com/products/69-zoneflex-r600#firmwares