On December 24, 1773, Ludwig van Beethoven, the Kappelmeister, died. It was believed that Johann purposely falsified his son's age, wishing to make him younger by two years (with Mozart's career in mind). But, the grandfather's death supplies ample proof that the young Beethoven could not have been born in 1772 and still retained so many personal and warm recollections of his beloved grandfather.
Johann attempted to apply for his late father's post, but was unsuccessful. This may be one of the reasons for his bad temper and drinking habits.