Hi Jan
They say the Fall (Autumn) because in Israel the Secular Calendar starts in the Autumn, the 7th month Tishri turns the year. The Ecclesiastical Calendar starts in Spring and the 1st month Nisan turns the year.
The Bible does not use the Secular Calendar, it uses the Ecclesiastical one.
Looks like WT thinks Adam was created in the Autumn. So by their calculations he must have gone hungry for a bit as he went through Winter.
(Genesis 1:29) . . .And God went on to say: “Here I have given to you all vegetation bearing seed which is on the surface of the whole earth and every tree on which there is the fruit of a tree bearing seed. To you let it serve as food.
Maybe they think he had some pumpkins to eat. And maybe they think that newly created Adam appreciated autumn colour, was happy with windfalls and liked kicking piles of dried leaves.