I find that, if I begin watching a recording of a programme before the broadcast of the programme has ended, fast-forwarding to hitting the current end of the recording results in being dropped out, instead of being returned to normal play. This didn't happen with our previous STB (a Humax Freesat box) so why should it happen with the BT box, which I believe is also manufactured by Humax? It's doubly annoying because the state of play isn't preserved, which means the playout of the programme returns to the beginning. My box has up-to-date software, in case anybody thinks to ask.
The workaround is to use the number buttons to skip to part-way through the recording. In this case press 9 to get to 90% of the way through then use Skip Forward a minute at a time and / or carefully fast forward at slowish speed (6x work best for me) to within 10 seconds or so of live.