An insured took a Product liability policy with retroactive date 01.01 2015. The sum insureds per event and aggregate were $20,000/- and $60,000/- respectively. 

A claim was reported on 18 July, 2020 about a loss of o $ 20,000/- which took place sometime around November 2016. Meanwhile, the insured increased the sum insured in 2017 and chose $45,000/- and $75,000/- for per event sum insured and aggregate sum insured respectively. 

a) Expound with examples, the manner in which the above claim will be assessed in case of Full Prior Act policy?  What would be the amount paid? Advise your underwriter the appropriate steps that should be taken at the time of enhancement of the sum insured. 

b) Describe the manner in which, this claim be assessed in case of Prior Act policy?