Think you are right but you may need to take some action to meet the shortfall in your endowment mortgage. The £25k you are short in that will need to be made up somehow. You mayhave to consider either a new repayment mortgage or adding that to your existing repayment mortgage, unless you have some other way of meeting the shortfall. The £25k won’t just continue as a mortgage automatically, if your endowment mortgage has matured, you’ll need to do something to cover any shortfall.
(should add I’m not an Ifa though)