"This case also showed that complaints are increasingly made by people who didn’t watch the programmes"
How can they substantiate this? As per usual on the guardian it's all waffling political nonsense.
They presumably have an idea what the "normal" lag between broadcast and complaint is; if you can file complaints 24h/day through the website, and most people complain in the hours following the broadcast, then you can determine that complaints made later were news-driven.
Heck, I've done this myself once, for the broadcast of the Enoch Powell speech recently.
Powell's speech was interspersed with commentary, If you didn't listen to it then your complaint should be invalidated