Is Glasgow not due to get an Air Europa B738 as it's 6th aircraft?
Also, on analysis of Edinburgh destinations(by day & route) and seating charts for flights, it looks like a second B738 will be based there from the end of June 2016. On every day except a Tuesday & a Thursday, there is a requirement for 2 B738 due to flight distances, which a B733W would not manage without a fuel stop.