All the cheap bread is baked in the same places. It just has different packages on it just like the cheap cereal and biscuits.
I'd often go up to the bakery at Wakefield chat to the Tesco driver there, deliver the load to the Aldi warehouse in Manchester and collect empties trays from the Morrissons warehouse on the way back down.
Waitrose and probably others use part baked bread which has been frozen, collected by the lorry load from Theale (iirc) and delivered like that.
The crispy warm bread that everyone likes has come from their freezer then "baked in-store" for when they need it.