See 'WikiDevi' @ the Internet Archive (MW XML, Files, Images)
upgraded MW to 1.30 - maybe things are slightly less broken
Roku Relay (2200X)
Wireless Range Extender
Most useful FCC documents are under short-term confidentiality until 02/11/2020.
FCC test report documents only mention 40 MHz channel bandwidths but that may just be what they tested with and it could still support 80 MHz bandwidths for 802.11ac. The documents mention "Chain 0" and "Chain 1" for both radios which suggests 2x2:2 operation.
- How do I set up Roku Relay? at Roku Support