Asus has now released an update to replace the buggy firmware version 3.0.0.4.385.20457 for the RT-AC88U.
The new version is 3.0.0.4.385.20490
I had to first factory reset my RT-AC88U (since I could not login any longer), go through a few setup screens, and then I logged in and performed a...
Do not use this version of the firmware. It will lock you out of your router if you have it set for secure https access to the login page, and there is no way to downgrade the firmware without first resetting the router to factory defaults.
I filed a case with them, and today Asus has removed...
And now firmware version 3.0.0.4.385.20457 has been removed from the Asus support site downloads. But no new firmware yet for those of us who are stuck with this dud version after having installed it, other than to factory reset and downgrade.
I have also experienced the exact same problem. I have https access configured on my RT-AC88U, and as soon as I upgraded the firmware to 3.0.0.4.385.20457, I was no longer able to reach the router login screen. Instead, there is an error message about being unable to securely connect to it...