Demolition of existing dwelling (retrospective) and erection of dormer bungalow with a conservatory to rear

Change of use of single-storey workplace building from business use to 2-storey annexe building (2 x 1-bed annexes) ancillary to existing dwelling involving raising the height and insertion of dormer windows, replacement of existing workplace door with door/window, erection of conservatory to rear and installation of external staircase (part retrospective)