Having legal opinion is a simple step by step qualification and review exercise which should be conducted by all mortgage holders to determine, beyond any shadow of a doubt, that
a) the bank/lender has been granted the right to act as if they were you, under a Power of Attorney or similar authority and authorised by you to sell or transfer their legal and equitable rights to the mortgage and/or proceeds;
b) the bank/lender actually used the Power of Attorney to sell/transfer the mortgage under a securitisation process without telling you; and
c) when the bank/lender had sold/transferred the rights of the mortgage, did they retain both legal and equitable rights to continue to hold a valid charge on your property.
Eight out of ten UK mortgages have been sold on. Yours could be one of them.