Simplify the following text for a Grade 8 native English-speaking person.
Original: He was then assistant organist at Southwark Cathedral from 1923 until 1925 , before moving to Keble College , Oxford ( where he was also Organ Scholar to continue his education ( 1925 to 1928 ) .
Simplified: He was assistant organist at Southwark Cathedral from 1923 until 1925 . Then he continued his education at Keble College , Oxford .