I thought ATV effectively finished when the IBA forced them to sell 51% to local investors, resulting in them becoming Central on air and the holding company becoming ACC, and that Court took over after Lew Grade was ousted by the board of directors in the aftermath...?
Getting back on topic, I remember the change from Pye to PRT - some labels from around that time have obviously blacked out Pye logos and PRT lettering stamped nearby (don't think I actually own any but one sees them around often enough).
And speaking of Pye, here's another favourite of mine: