Back in 2018, Channel 4 removed its Channel 4 HD channel, and their on demand All4 service from Freesat, apparently due to a dispute over carriage fees.
(Although you could manually add Channel 4 HD back to your Freesat box – https://www.satandpcguy.com/2018/02/20/how-to-add-c4hd-to-your-humax-freesat-box/ )
However, today, it appears that Channel 4 HD may soon return to Freesat.
It has been reported that Channel 4 HD, and some of their music stations, Box KISS Magic Kerrang!, have now been added to a Freesat Service Description Table (SDT), which is used to identify services contained in MPEG transport streams.
And this could also mean the return of the All4 streaming service on Freesat boxes (although a VPN & Smart DNS service will be needed to access the “for UK only” content from outside the UK.)
This could be down to how Freesat and its “tv aerial” equivalent Freeview have now been “consolidated” together.