Re: The thing is... it's nothing new.
The likes of ITV and Channel 4 force their ads when using their catch-up services. They disable the FF key specifically.
It's doubly annoying if you have a flaky connection, and replay gives up late in the programme. You are then forced to restart from the beginning because of their rubbish coding. Attempt to go to where you left off and you have to sit through the "ad breaks" from scratch again. Hoorah for the Mute button.
Every Freeview PVR that I've seen allows fast forward in recorded content, where it can't spot the difference between programme and ad, so that's my preferred option.