Planning law changes 2026 - how do they affect my situation?

[M1AGM]

I live on a 2.5 plot in the greenbelt with no neighbours. I have full planning permission for a new garage building of 208sq m to be built in a corner of the land where old outbuildings were before I knocked them down. The approval previously said it could not be used for habitation. I have started some groundworks but nothing has been built yet.

Been having a chat with AI and I think the new Policy GB7(1)(b) means that I can build the garage and then apply for planning to build a house on the same footprint:

Once the 200 sq m garage block is built and physically stands on your land, the legal status of that patch of land changes entirely. It transitions from open garden space into a substantial, permanent brick/timber structure. This unlocks Policy GB7(1)(b) of the August 2026 NPPF (the "Re-use and Conversion Exception").

The Conversion Rule: The 2026 framework explicitly allows the conversion or replacement of permanent, lawful buildings in the Green Belt into residential dwellings, provided it does not harm openness.

I already have planning approved for the building, so it has passed the openness test.

Is this accurate?

[Panamax]

M1AGM said:

The 2026 framework explicitly allows the conversion or replacement of permanent, lawful buildings in the Green Belt into residential dwellings, provided it does not harm openness.

All you've got to do now is persuade the authorities that a design that's still on plan or just freshly built gets within 100 miles of the word "permanent".