Mixed news for FTSE 250 transport firm Go-Ahead as it is shortlisted to bid for the new Thameslink franchise but is not invited to bid for the Essex Thameside contract.Thameslink is a multi-billion pound project providing new and longer trains between north and south London. Essex Thameside connects London, Tilbury and Southend and is a major commuter artery. Go-Ahead says it will be seeking feedback from the Department for Transport on the failure.Go-Ahead already operates the Southern, Southeastern and London Midland franchises through its 65% owned subsidiary Govia.Since the beginning of the year Go-Ahead has dropped 5.8%BS