Simplify the following text for a Grade 11 native English-speaking person.
Original: With the construction of the Jubilee line Extension , the opportunity was taken to introduce new trains , and today the line is worked by 1996 stock , which has an exterior similar to the 1995 stock in use on the Northern line but ( in spite of the confusing naming ) is technically less advanced .
Simplified: With the opening of the Jubilee Line Extension , the opportunity was taken to introduce new trains , and today the line is worked by 1996 trains .