Thanks for that, Robert - great to know that this feature is in the pipeline for the next stable release.
For the time-being, I am getting round the problem by cancelling upcoming episodes that I know I have already watched.
A bit time-consuming and I assume that cancelling them means that they will be reschedules for a future date, but is an acceptable way of dealing with things until I move on to 4.3.
Out of interest, is there any chance that 4.3 might be adding the facility to specify what seasons to record?