At any point in a PCH/Lease it's any difference between what the insurance company pays out and the outstanding lease settlement amount (without the car being handed back if a write off) that's the issue. This could, potentially, be greater in second and subsequent years although probably not so much of a
problem in the first year. The finance companie's value of the car could differ from the insurance companie's. Hence the gap....
Also, the initial "deposit" isn't covered by standard insurance and if you need to start a new lease then you'll have to find this again too (if significant - depends on the individual lease) - and that's even an at cost add on on most GAP policies...