It's unlikely that there was anything from Roku pushed out that caused anything. There hasn't been any OS updates in over a month from what I've seen.
For wireless connections, Roku devices that use the 5 GHz WiFi band have channel restrictions. There is a group of channels that are labeled DFS, and Roku devices will not use them. If your router is configured to auto-assign the channel used (and virtually all are by default) it might have changed to an NFS channel. So no Roku device can use a channel numbered between 49 and 148.
For the 2.4 GHz band, Roku supports channels 1-11. Most routers don't offer any different channels, but there are some that have other channel numbers. If your router changed to a channel outside that range, it won't be seen either.
Dan
Roku Community Streaming Expert
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