It may interest you all to learn that the proposal for the restoration of the railway line between Cheltenham and Kingham is NOT the only "Satellite" railway line to East West Rail proposal that is advocated privately.

There's also the proposal to restore the (Cambridge) Shelford to Sudbury line closed down on 06 March 1967. 

This would enable through trains from Colchester to East West Rail at Cambridge.

In the same way as there are services from Ipswich and Norwich to East West Rail at Cambridge.

This proposal started in 2014 with a local  newspaper article

https://www.eadt.co.uk/news/21718353.haverhill-colchester-campaign-reopen-railway-line-colchester-cambridge-via-haverhill-gathers-steam/

There has been some support from RailFuture

https://www.railfuture.org.uk/article1483-Haverhill-campaign 

https://www.railfuture.org.uk/display3806 

https://www.railfuture.org.uk/display3729 

The proposal has had a chequered online history with Facebook page called "Cambridge to Colchester Railway Campaign" coming and going, and recent emphasis on the section from (Cambridge) Shelford to Haverhill rather than the full length of the line.

However railway restoration to Haverhill has had local political support

Sadly the Chairman of the Cambridge to Colchester Campaign died very recently

https://www.legacy.com/uk/obituaries/suffolkfreepress-uk/name/malcolm-hill-obituary?id=58894293 .

There is still a Twitter feed about the proposed rail restoration https://x.com/railhaverhill?lang=en 

There have also been calls for a guided bus way to be built instead

https://www.bbc.co.uk/news/articles/cgrjr8vpj9no 

There has been some criticism of this idea

https://eastangliabylines.co.uk/business/transport/call-to-ditch-busway-and-open-new-haverhill-train-line/