Original sentence: Although 2004 should have been the year the modern electrified rail network opened, opening dates were pushed back many times and, currently, 2018 is the deadline.The Domokos to Thessaloniki part opened, although unelectrified, in 2004, and the Athens to Kiato line in 2005 up to Corinth and in 2007 up to Kiato, once again, unelectrified
Edited sentence: Although 2004 should have been the year, when Greece would finally have had a modern, electrified rail network, the opening dates were pushed back many times and, currently, 2018 is the deadline.The Domokos to Thessaloniki part managed to open, although unelectrified, in 2004, and the Athens to Kiato line in 2005 up to Corinth and in 2007 up to Kiato, once again, unelectrified