Unfortunately I can't see them keeping it open much longer with just 3 aircraft, especially when you mention the EMA base and factor in how the other airlines will become the bigger players there, namely Jet2.
If this is the case I can see EZY expanding/opening a crew base up at DSA. The amount of passengers from the North East, Newcastle / Sunderland / Durham areas etc that travel on EZY (plus numerous others) flights from DSA could perhaps sway them in this direction to perhaps expand on the base.
It does make you wonder, with the reduction in aircraft at many bases and more aircraft on their way, where all these new aircraft are going to be deployed.