No the misfire under these particular conditions manifested about 1000 miles after the spark plugs were changed.
When I bought the car, the previous owner had obviously neglected the plugs because after about 4 weeks of ownership I started to get a random misfire at high revs, which was sorted by changing the spark plugs. I'm hoping that by previously neglecting the plugs and causing them to break down, it put more stress on the coils which is why I'm now getting the issues I am. At least then it's any easy fix to diagnose and sort.
The good news is that I do now have a permanent EML so a code has been logged so just need to get my reader on it tomorrow.