Life insurance Sanity Check (Cancel & Re-apply now or leave)

20vt-rs

Hi all...
Quick sanity check on life insurance, would appreciate feedback or things I should think about please: Currently I have separate policies for my wife and I, both run for another 13 years until I am 60 and she is 56. We have one dependent who will be around 20 when these policies run out, and we are just about to clear our mortgage.
I am thinking ahead and considering extending the life insurances to my retirement (+7 years), because it is likely we will move in the next few years, and therefore have a mortgage, probably until retirement.
The current policies cannot be extended, and we will need to cancel those and take out new ones. My thinking is that taking out new policies now would be better than waiting 13 years and then taking short 7-year policies, would that be fair to assume? 
I have gathered quotes on the same basis as we have now, which would cover the maximum mortgage amount we'd consider, overall the increase for both is approx £10 per month, giving us the additional 7-years cover. Does this sound reasonable? Joint cover actually seems a few £ more, so would like to keep separate for cost, and also keeping cover should the worse happen for one of us.
Is there anything else I need to consider, is the plan to extend things good or would we be better leaving as is and saving the extra £10 per month, just want to make sure I am thinking about everything!
Thank you