Orbi RBR750 Takes Forever to Load Admin Screen

You have probably tried Cure #1 (to any technology problem), turn it off and back on again.

Clear the browser cache, then connect to the orbi.

Cure #2 is a Factory Reset, which most of us imagine is like the world's longest enema.  Those lucky souls who (literally) did nothing to set up their Orbi besides changing the WiFi name and password can do this in under 15 minutes.  In my case, I have customized almost every possible setting: DNS servers, DHCP ranges, assigned IP's to devices, created custom devices names and types, setup DDNS, enabled OpenVPN, etc. etc.  I do a Factory Reset in two stages:

Stage 1: Save a copy of the configuration. Get out paperclip and do the Factory Reset.  Connect to the Orbi and begin configuration.  Do not change the WiFi SSID. When I get to the place where there is a choice of "continue setup or load a previously saved configuration", I load that saved config file.  After this, the Orbi reboots, which changes the SSID, and all my devices begin to connect as I wanted them to.

(Do my Lucky Dance)  Is the problem solved.  YAY

Stage 2.  If that did not resolve the problem, then do a Factory Reset and type in everything from scratch (after making screen shots of every setup page).  This takes over two hours. and the family is screaming the entire time.