"The NPPF attaches great weight to conserving landscape and scenic beauty in AONBs."

There is pressure on 'green belt' across the country:
Futures Forum: The NPPF under pressure: building houses on green space

But with a review of the National Planning Policy Framework ongoing and with an election less than a year away, things might change:
Futures Forum: The Save Our Green Spaces campaign: greenbelt under threat

Indeed, the Chancellor and the Communities Secretary are encouraging development on brownfield sites:
Futures Forum: Housing crisis - what housing crisis? ... "Evidence for a UK housing shortage is hard to come by."
Good news for the green belt as George Osborne plots ways to encourage building on brownfield sites - Telegraph
Eric Pickles unveils plans to help protect Britain's greenbelt | UK | News | Daily Express

However, Sidmouth might well be having 250 new homes on its AONB belt:
Futures Forum: Housing crisis in Sidmouth - what housing crisis? ... "Evidence for a housing shortage is hard to come by."

On the other hand, the decision by a planning inspector to turn down new housing in neighbouring Newton Poppleford might well have an impact further afield:
Newton Poppleford: appeal to develop Badger Close – dismissed with EDDC’s appeal for costs refused | East Devon Alliance

NEWTON POPPLEFORD: BADGER CLOSE – A LAYMAN’S SUMMARY

18th June 2014:

Character and Appearance – Area of Outstanding Natural Beauty (AONB).

Since the proposed development would be approximately 5% of the size of the existing settlement, the Inspector concluded that in the context of the village, and in the light of the scheme’s visibility from a main approach road, it would be a significant addition. Under these circumstances (NPPF para 116) major development should only be granted in AONBs in exceptional circumstances.

The Inspector considered that the appeal scheme would result in a substantial adverse impact in the short, medium and long term in respect of a number of viewpoints. The first of these viewpoints is of particular significance, as it relates to an important approach into the village. As such, he concluded that the area’s character and appearance would be unacceptably harmed, to the detriment of the natural beauty of the AONB.

Overall Conclusion

The appeal scheme represents a major development in an AONB and within the NPPF planning permission should therefore be refused except in exceptional circumstances and where it can be demonstrated that the scheme is in the public interest. The Inspector noted the development’s contributions to meeting general and affordable housing needs would represent positive benefits. However, the AONB does not extend over the whole of East Devon District and, as such, there are likely to be opportunities to meet District-wide needs in locations that do not adversely affect the AONB.

Nevertheless, bearing in mind, first, that it is an underlying principle of the NPPF that patterns of growth should be actively managed to make the fullest possible use of public transport, walking and cycling, and focus significant development in locations which are or can be made sustainable and, second, that the NPPF attaches great weight to conserving landscape and scenic beauty in AONBs, the Inspector considered that his conclusions on the two main issues in this appeal were sufficient to overcome the advantages that would result in respect of the provision of general and affordable housing. The exceptional circumstances that are required by the NPPF for granting permission within an AONB have not therefore been demonstrated.

Newton Poppleford: Badger Close – a layman’s summary | East Devon Alliance

And in another ruling, another developer has been refused permission to build - despite lack of a five-year housing policy:
Developer loses fight to have large site included in local plan | East Devon Alliance
High Court backs underproviding core strategy on basis of planned review | Planning Resource

In a further posting from the EDA, there is a telling comment about the construction of Cranbrook - on primary agricultural land - in the context of 'short-term' fixes responding to the pressure to build more housing:
Royal Town Planning Institute mentions East Devon in its submission to Parliamentary review of NPPF | East Devon Alliance
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