NMS300: No scheduled backup of switch config via encrypted connection?

Hi everybody,

we are using the scheduled backup feature of NMS300 to automatically backup the config of our switches to avoid a manual backup of the config after every configuration change, but this seems to work only via telnet. I've created ssh- and https-credentials, which definitely work when used to connect to the switches manually, but when associated to a test switch, the NMS300-backup doesn't work for this switch. The error message is "No valid telnet credentials". When valid telnet credentials are associated to the switch, the backup works.

I have reported the same problem back in 2016 for our M4100 switches, and the answer was that this behavior was by design:

https://community.netgear.com/t5/Managed-Switches/NMS300-config-backup-with-telnet-disabled/td-p/1161992
Meanwhile we have replaced several of our M4100 switches with M4300 series, but the problem remains the same. We are using NMS300, version 1.7.0.22

Is this some kind of configuration error or is the backup feature still limited to telnet? If so, are there plans to change this?
Thank you!

Best Regards
Christoph