This blog relates to sale/purchase transactions, its common for developers to get planning consent before purchasing.
Just getting planning consent doesn’t trigger a change, its the use at the effective date of the transaction that overrides any past or intended future uses for the property.
The Rules are in
Meaning of “residential property”
(1)In this Part “residential property” means—
(a)a building that is used or suitable for use as a dwelling, or is in the process of being constructed or adapted for such use
a building designed as a dwelling or number of dwellings or intended for use solely for a relevant residential purpose
In most cases, there will be no difficulty in establishing whether or not a property is residential property.
Use at the effective date of the transaction overrides any past or intended future uses for this purpose.