National Planning Guidelines: Revision date: 06 03 2014
"Should mineral planning authorities take account of the environmental effects of the production phase of hydrocarbon extraction at the exploration phase?
Individual applications for the exploratory phase should be considered on their own merits. They should not take account of hypothetical future activities for which consent has not yet been sought, since the further appraisal and production phases will be the subject of separate planning applications and assessments.
When determining applications for subsequent phases, the fact that exploratory drilling has taken place on a particular site is likely to be material in determining the suitability of continuing to use that site only insofar as it establishes the presence of hydrocarbon resources."
So that means you can't look forward to consider whether the 2nd and following steps would be acceptable, but once the first step is taken, the second step should be allowed. Now how did those regulations suddenly come into being?