Hitler had been held back a year?

Does "Hitler had been held back a year" mean something like "(for example: Hitler had been moved from grade 5 to grade 4)"?

Context:
Jewish background and Hitler[edit]
Further information: History of the Jews in Austria
There is much debate about the extent to which Wittgenstein and his siblings, who were of 3/4 Jewish descent, saw themselves as Jews. The issue has arisen in particular regarding Wittgenstein's schooldays, because Adolf Hitler was at the same school for part of the same time.[65] Laurence Goldstein argues it is "overwhelmingly probable" the boys met each other: that Hitler would have disliked Wittgenstein, a "stammering, precocious, precious, aristocratic upstart ..."[66] Other commentators have dismissed as irresponsible and uninformed any suggestion that Wittgenstein's wealth and unusual personality may have fed Hitler's antisemitism, in part because there is no indication that Hitler would have seen Wittgenstein as Jewish.[67]
Wittgenstein and Hitler were born just six days apart, though Hitler had been held back a year, while Wittgenstein was moved forward by one, so they ended up two grades apart at the Realschule.[68] Monk estimates they were both at the school during the 1904–1905 school year, but says there is no evidence they had anything to do with each other.[69] Several commentators have argued that a school photograph of Hitler may show Wittgenstein in the lower left corner,[70] but Hamann says the photograph stems from 1900 or 1901, before Wittgenstein's time.[71]
In his own writings[72] Wittgenstein frequently referred to himself as Jewish, at times as part of an apparent self-flagellation. For example, while berating himself for being a "reproductive" as opposed to "productive" thinker, he attributed this to his own Jewish sense of identity, writing: "The saint is the only Jewish genius. Even the greatest Jewish thinker is no more than talented. (Myself for instance)."[73] While Wittgenstein would later claim that "[m]y thoughts are 100% Hebraic,"[74] as Hans Sluga has argued, if so, "His was a self-doubting Judaism, which had always the possibility of collapsing into a destructive self-hatred (as it did in Weininger's case) but which also held an immense promise of innovation and genius."[75]

MOre:
https://en.wikipedia.org/wiki/Ludwig_Wittgenstein#Jewish_background_and_Hitler