Complex sentence: However, the trains were not scheduled to drive following a schedule, they will be driving on routes where they're needed instead, in many cases they will be seen on the same routes as they were driving on in 2015.
Split into simpler sentences: However, the trains were not scheduled to drive following a schedule; they will be operating on routes where they're needed instead. In many cases, they will be seen on the same routes as they were driving on in 2015.