But two such outages at facilities that serve the same purpose and just months apart?
Two outages for different reasons, perhaps. The power system in Britain may be a bit decrepit (like ours) and that may have been the cause.
I do not want to rule out an attack, but I also don’t want to jump to such a conclusion without more info.
Its out due to computer problems caused by the terrible UK weather. Areas in the UK have had over 5000 lightning strikes this week. Add to that 80-100mph winds, driving rain, sleet, hailstoes, and 50ft+ waves.
The bad UK weather has been well covered on FR.