JP
The first thing to say is that you do not need to apply for NS ESA to maintain your State Pension, UC pays Class 3 NI Credits which count towards the pension.
NS ESA does pay Class 1 NI Credits which may allow you to make another claim for NS ESA if the first is time-limited, it is not if you have LCWRA, but there is no other advantage.
If you do apply for NS ESA then your current UC LCWRA award should be applied to the new claim automatically, so no assessment.
Gordon
Nothing on this board constitutes legal advice - always consult a professional about specific problems 
