The epithet fits Andronicus II better than Andronicus III, who was not very pious

All we know of him [Andrew, governor of the Peloponnese] is that he was appointed by 'the pious Emperor Andronicus' - the epithet fits Andronicus II better than Andronicus III, who was not very pious, but it was often given formally to emperors, regardless of their characters - and that he was the father of a saint, Leontius of Achaea, who was noted for his good works later in the century.

S. Runciman, Lost capital of Byzantium (1980), 48