Complex sentence: Surrey Quays station (and the entire East London Line) is currently closed as of 22 December 2007, and will not reopen until June 2010 when it will become part of the new London Overground system.
Split into simpler sentences: Surrey Quays station (and the entire East London Line) is currently closed (closing on 22 December 2007) and will not reopen until June 2010. It will become part of the new London Overground system.