A total layman here though easy to imagine that if the plug was...

A total layman here though easy to imagine that if the plug was drilled out between zones then that would make the pressure drop as in simple terms the hole is (1) larger and (2) the zones concerned are fathomably larger than one zone.
The way I sense things regards artificial lift and economics of the situation is that there would be an associated cost of the N2 or nitrogen as well as the cost of pressure injection via a compressor and diesel or power to drive it.
The initial amount of N2 is however I suspect not totally finite as there would be undoubted losses but the N2 could be generated via an osmosis plant or similar from atmosphere considering the fact atmosphere has 72% nitrogen within it.
I think its all good if hydrocarbons are present and the poo price holds up.
Just having a stab at it due to my instrumentation experience.
Suspect an update tmozz hopefully it will be positive then it was and is a always risky game to play