Vigor2865ac, 4.5.2.2_BT

When accessing the Router via the web interface, the login screen appears quickly but once the credentials are entered it can sometimes take minutes for the UI screens to appear.  This is not new in 4.5.2.2_BT - it's been like this for a while.  Sometimes a reboot is the only way around this.

Have tried the usual web browser actions of clearing cache and cookies.  Doesn't seem to make a difference.

CLI access does work fine while GUI access is being slow.  Router's CPU usage is about 2% but memory use is 93%.

Yeah, sad to say that ac range is a real dog in so many ways, move up to ax if you can.

Updating to an ax version would seem to require new mesh APs since the 912s aren't listed as compatible with the ax version so not really desirable to upgrade.
Is it the case that the ax version has greater cpu / memory - it's not entirely obvious from the data sheets what the actual hw difference is.