It was primary school for me too. I vaguely remember the advert but the sole reason that I remember it at all is that it became common to say "awwww but I'll be your best friend" to get something you wanted... in reference to the ad.
I didn't start primary school till 1985 though so it was definitely after that. I'm thinking most likely 87/88.
Where did you find the Rolo ads Peter? Are you sure you watched them all?
I've also been trying to find the 80s cherry coke advert. It MAY have been early 90s though.... "Cherry coca cola, cherry coke, cherry coke.... it fizzes right out of your mind. Something something start of it, it's a new twist" etc.
I know, I know, it's sad lol.