So, yeah, it's been the evening... which means tea making around Britain! So, I've had a look back at the frequency data for this evening...
A dip in frequency at 8.30pm and 9pm is clearly visible - as are smaller dips on the quarter hours. So, unless it's luck, at least my device isn't just showing noise :) I'm strangely excited by this - I love it when theory and what we're told is true :)