quote :- "
A friend of mine said it was due to the number of heli's going to the Morecombe bay gas fields " 
The heli's do not effect the GA operation at Blackpool at all , your informant has simply made an error .
All I can think is that their is a protected zone around the Offshore Oil and Gas Fields and thats it , and GA traffic calls up regularly on their company frequency for crossing clearance , and 99.9% of the time GA gets cleared through.
The offshore helicopter operation has no impact on GA at Blackpool as it is a self contained operating unit