The form required for a review (neutral word) to increase both the mobility and care components, will either be a DLA434 or a DLA580.
If my memory serves me correctly, as I haven't seen these forms for a long time, there are two parts these being the mobility and care sections. If an increase in the care component is being requested, there is no need to complete the section relating to mobility. Indeed, to do so may result in the pre-existing mobility component being looked at again.
In order to apply for the care component to be increased, a written notification should be sent to the DLA Unit at Blackpool. The postal address is:-
Disability Living Allowance
Warbreck House
Warbreck Hill Road
Blackpool
FY2 OYE
Nothing on this board constitutes legal advice - always consult a professional about specific problems