Ken Reid competitions for the Irish paper

[klakadak-ploobadoof]

Some time ago in the thread on Frankie Stein strips by Ken Reid I brought up the topic of the long-running series of competitions Ken drew for Irish editions of the Sunday Express (the introduction in Fudge and the Dragon reprint from Savoy Books offers a tiny bit of information about the competitions mentioning the names of a few series: Horse Clues; Horse Pics; Titles; Inn Signs). Generally, there is very little information about the competitions, although they ran for more than a decade.
After a thorough search, I can now show a few samples. The images below are of the original artwork. I am now wondering what sort of competitions they were and how they were used in the paper. Were they like multiple-choice puzzles where readers were to pick the correct name from a number of options provided? Some have envelope E, G, etc., some are dated, others aren’t. It is intriguing how it worked; it looks rather complicated at first glance... Would anyone here know?