There is beta software available for the VTM35 (1.01r3) which ups the Matter version to 1.5 and seems to fix the disconnect issues.
It’s easy enough to install if you are using Home Assistant. It’s available via the DCL testnet so all you have to do is enable the “Enable test-net DCL usage.” on the Matter Server configuration page and the beta release will appear so you can upgrade the switches within a day or so.