Also have this issue. Accessing the adaptor web gui page using Safari on both MacOS and iOS forces all adaptors on my network to restart. Chromium based browsers on Windows, Mac and iOS all work fine. Have 5 MA2500D adaptors all on 2.0.11, all using stock settings apart from static IP addresses.

Received the letter around two months ago, nothing since..

@Mark Reid I got a similar invoice just ignore it if you have already received the items!!