Thanks for the response. I don't subscribe to Maxit/Full House TV, but have been able to watch two and a bit series of FBI without a hitch - so like you, I think somebody has mis-labelled this episode.
I've had problems with other series, mostly random episodes that don't appear, or (less annoyingly) episodes appear with write ups that clearly relate to something else entirely. I'm not sure if humans are involved in running the catch up service or if it is Artificial (un)Intelligence but whichever it is it is bloody annoying. Trying to get a sensible response about this from Virgin's help has wasted a lot of time to no good purpose.
Anyway, thanks again. I'll live without knowing what happened in episode 4!