I would like to know what "a guy from the year below" means in the following sentences:
At mealtimes I sat with Karolina and Beata, a friend from lectures. She was short and round-faced and busty, quick to laugh and quick to be frightened. She told us she was getting married right after the camp was over, to a guy from the year below.
‘You’re not pregnant, are you?’ asked Karolina, looking concerned.
‘God, no!’ cried Beata, blushing a little.
In this novel which is set in the 1980's in Poland under the socialist regime, where homosexuality was socially unacceptable, the protagonist Ludwik (a university graduate) left Poland in 1981 to live in the United States of America. And he remembers what it was like back then in Poland, where he went to the agricultural camp (which was mandatory for college graduation). At the camp, he sat with his friends Karolina and Agata during mealtime. Agata told them that she would marry "a guy from the year below" after the camp.
In this part, I wonder what this expression means. Would that perhaps mean that she would marry a guy who is a third-year student, because she is currently a fourth-year student? Or would that mean that she would marry a guy who is younger than her by one year...?
I am an English learner from South Korea, so thank you for your patience in advance as I may not know obvious things. I would very much appreciate your help. :)