What is Sonos doing to restore access to BBC radio services in UK via Alexa?

I'm not sure you understand the relationships here.

Sonos is an aggregator. They don't supply any direct content, but instead provide a platform for other people to share their content. All Sonos does is point to other companies servers, which that company has set up to interface with the Sonos API.

It's entirely up to the other companies to make the choice to share their content on Sonos, but Sonos doesn't have any financial incentive or deal with these companies to leverage. All Sonos does is provide a larger audience.

Much the same as TuneIn, another aggregator of content, although TuneIn does indeed create some of their own content, the great majority of what they serve is other companies' content. Again, using a similar model to Sonos, all they do is point to other companies servers. Other than their Premium Content, they don't have a financial stake in those streams, so they also have no financial leverage to use.

So, Sonos and TuneIn are basically at the mercy of the BBC. It's the BBC that has taken these decisions to remove access from non-BBC controlled areas, so it's the BBC that you need to be complaining to. Companies like Sonos and TuneIn, and frankly Amazon (the Alexa portion of this discussion) are only providing access to the BBC stream, and not paying anything for it. So when the BBC decides to cut off this content, none of these companies have any leverage, such as saying "Hey, we gave you $10 Million for the rights to distribute this".

While I get that it's easy and convenient to complain about the situation here, because Sonos is kind enough to have a community forum to post in, the simple fact is that none of these companies have any leverage over the BBC, other than the audience size.

You've got a much better chance of getting your message to the managers at the BBC if you were to contact them directly. I doubt that they have anyone pulling data from this forum for presentation to their management

Yes, the BBC pulled their service because Tune-In was either not collecting or providing the corporation with the customer usage details of the BBC radio stations.

The BBC said they needed the data to help improve their services for their licence payers. I’m a licence payer and all I can say is it certainly has not improved my service (via Tune-In/Alexa/Sonos) thus far, but I have not yet fully explored any potential alternatives either.

Negotiations broke down with Tune-In and the plug pulled by the BBC.

It needs users who are affected to maybe write to the BBC.

Here are two useful links that relate to the issue:

https://www.bbc.co.uk/blogs/aboutthebbc/entries/37e4e3f6-fbd2-4c14-8d72-7f7139641582

https://www.theregister.co.uk/2019/10/01/bbc_tunein_radio_streams_pulled

There is a newer blog, I would suggest commenting at https://www.bbc.co.uk/blogs/aboutthebbc/entries/45fa0731-189c-43eb-8e4f-3071b8384895 instead

The Sonos device itself can still play Tunein and supports favourites. The skill needs updating so that its possible to invoke a tunein station or favourite on the Sonos regardless of Tunein being supported on the echo device processing the voice command.

I've created a petition at Change.org about the BBC removing TuneIn radio streams – please sign and share.
https://www.change.org/p/bbc-restore-bbc-radio-streams-to-tunein

This shouldn't be just about whinging to the BBC as individuals. I believe that Sonos (and Tune In) could be more proactive. Is it doing anything to represent the user base on this issue? Has it informed the debate on how many Sonos customers are affected? Has it advised any workarounds? Is Sonos seeking a UK alternative to Tune In, as is provided outside UK ? Can Sonos directly provide BBC with the audience data they require without reference to Tune In? Can Sonos provide direct access to BBC Sounds via Alexa?

I 100% agree. The problem was merely precipitated by the BBC removed from tunein on many devices including Echo. I can still get BBC from Sonos Tunein either by Sonos App or from the Smarthings integration which picks up the favorites.

When specifying a Sonos device as an output for a Alexa command, the interaction between Amazon Alexa and Sonos seems to be dependant on Tunein availability on the echo device itself - even though its only processing the command and "casting" it to the Sonos.

Therefore I think it's perfectly valid to request that Sonos allow either all Tunein stations to be initiated on the speaker or for favourites to be allowed, regardless of that tunein stream being available on the echo devices processing the voice command.

I 100% agree. The problem was merely precipitated by the BBC removing tunein from many devices including Echo. I can still get BBC from Sonos Tunein either by Sonos App or from the Smarthings integration which picks up the favorites.

When specifying a Sonos device as an output for a Alexa command, the interaction between Amazon Alexa and Sonos seems to be dependant on Tunein availability on the echo device itself - even though its only processing the command and "casting" it to the Sonos.

This is close, but not 100% accurate. Your voice command is sent to Amazon cloud for processing. That process interprets the command and determines whether it's valid or not. It does not simply recognize that the command is to play audio on Sonos and just pass the command on to Sonos without validation. So you can't do anything by Alexa voice command that Amazon doesn't consider to be valid, something it could do on it's own echo.

Therefore I think it's perfectly valid to request that Sonos allow either all Tunein stations to be initiated on the speaker or for favourites to be allowed, regardless of that tunein stream being available on the echo devices processing the voice command.

It would be nice if this were the case, but Sonos doesn't even receive the voice request from Amazon's cloud if Amazon doesn't consider it to be valid first.

Note that this applies for all smart skills. Normal skills, where you need to preface your command with "tell XXXX" (where XXX is the name of the skill)) don't have Amazon validating the skills first before sending it on to the skills server. Amazon's processing will recoginize the skill that's being invoked and just send it on.

None of us affected mind whether it's the Sonos skill or Alexa processing that must change to restore the capability of echo playing BBC on Sonos.

Its not possible to say "Tell Sonos to play XXX" as you're then told to use the "Play XXX on " syntax. If "Play BBC Radio 2 on Kitchen" is used then a non BBC Tunein station is played but for "Radio 5 Live" is just fails.

Unsurprisingly the Sonos skill is rated only 2.1 on Amazon UK.

You should read https://en.community.sonos.com/troubleshooting-228999/information-bbc-on-tunein-6830711

It's not within Sonos' capabilities to restore something that the BBC has withdrawn.

No mate, BBC has withdrawn local BBC playback from echo device not Sonos device.