Simplify the following text for a Grade 11 native English-speaking person.
Original: The Stanmore branch was originally constructed by the Metropolitan Railway ( now the Metropolitan line ) and was designated as the Stanmore branch of the Bakerloo Line in 1939 .
Simplified: The Stanmore branch was originally constructed by the Metropolitan Railway ( now the Metropolitan line ) and was transferred to the Bakerloo line in 1939 .