Soldato
An update on this for you - I've just tried to transfer my son's JISA into an account with better returns for it's last 2 years, and the original provider is refusing to accept the transfer request because my signature doesn't match the signature I signed 16 years ago when opening the account.
I've now got who knows how many hoops to jump through if I want to get the transfer done.
There's a good reason right there for only using digital accounts. That way you don't get any of that faff.
Hope you get it sorted.