Thanks, quisling, for your exposition of 16d (#30) - the only clue I couldn't parse.
I sailed through the puzzle right up to the last part of the endgame. Since this protest was a very long time ago, I could not recall the exact words used; I was working with the title of the Top 20 UK hit based on this incident which I could remember. Once I accessed YouTube, all became as crystal.
Thanks, Filbert, for an enjoyable, well-constructed puzzle. It would have been the cherry on the cake if the protester could have been included, appropriately placed on 9ac, 10ac in jumbled form - or a meltdown, so to speak!: more than half the necessary letters are already there.