Sound quality on catch up tv

[Covenant]

I watched Black Earth Rising a few nights ago on catch up and was struck by how much better the sound quality was compared to the previous week watched 'live'.
It was a more immersive experience with the surround and atmos speakers contributing a great deal to the presentation. I have noticed the same on Netflix but put it down to the processing method.
Is there any reason why ordinary tv should be different?

[Stratmangler]

The BBC use a lot of bandwidth for all their other broadcast data on their multiplex on Freeview.

[Pigmy Pony]

Ah so it wasn't my imagination - I have occasionally noticed SQ to be better on catch up than live broadcast.

[Stratmangler]

It was not your imagination.
Sound quality on both Virgin and Sky is far better than on Freeview. IIRC Freesat is too.