sash windows in conservation area

Family member has a property in a conservation area which has wooden sash windows.
They have applied for planning permission to replace with upvc casement windows which as been refused

"The proposed windows, by reason of their material, would represent harm to the character
and appearance of the Conservation Area. As such, the proposal remains
contrary to policies S1, S2 and EN5 of the Local Plan 2013-2033 as well as
the Conservation Area Character Appraisal document."

The attached pics show the property - no 4 (blue door), no 2 next to it and the rest of the properties across the road, most of which have upvc casement windows, but none appear to have planning permission.

Any likelihood this could be successfully appealed and / or appoint a 3rd party who specialise in appeals ?

Thank you