RBR50 Router Firmware Version V2.0.0.74

I did not experience the loss of the "Advanced" tab. From what I see on this forum a NVRAM reset (don't have the exact instructions) and Factory Default Reset are the best things to do after the 2.0 upgrade. Do a basic setup and do NOT load in any saved settings from a saved configuation file.  Other users are also saying not to do any speedtests in the admin panel and to try disabling Daisy-Chain.  Good luck! https://kb.netgear.com/31486/How-do-I-reset-my-Orbi-system-to-factory-default-settings