[ASnep]

DVB-S2 is the modulation standard for HD, although DVB-S can he used for HD I don't think it's the done thing.

I doubt they'd need to negotiate with Astra, as long as the uplink is on the right frequency, not putting out too much power and conforms to their technical standards they don't care what is done with it. For the changes to happen they'd need to know as the uplink needs to be cut and brought back up

They may need to bother SES because on Astra2 DVB-S2 tranponders tend to be wider with a symbolrate of 23000 instead of 22000. But then again if Jimbo is right they will switch and the data in the EPG just reflects what the transponders are looking like now and not how they will look.