From May 1986: a MARVEL UK house ad touting the imminent arrival of the combining SPECIAL TEAMS (how long did it take the Hasbro Brians Trust to come up with that name?) in the TRANSFORMERS comic.
The push, of course, coincided with the launch of the toys themselves in UK stores. Their UK debut happened earlier than their official arrival in the reprinted American strips so Simon Furman and the Annex of Ideas had to concoct a new tale (Buster's dream) to tease the characters without wrecking continuity.
The free gifts (bankrolled by Hasbro) were also, of course, geared to making the new toys top of kid's gifting wishlist. Unleash the pester power!