The introduction of a new currency needs to account for customer deposits and loans and the Sterling pensions guarantee.
Consumer Deposits. The Scottish Reserve Bank (SRB) will issue the new S£ to your bank for onward transmission to your new bank account. The SRB will buy your old sterling from your bank and keep it, pro-tem, in an account of its own at your bank. This has no effect on the sterling deposits of the bank as they have simply changed ownership and thus moved from one bank account to another within the same bank.
Consumer Loans. There will be no official action to force people to convert loans into the S£ but you will be encouraged and probably prodded to do so. Banks that wish to operate in Scotland will be required as part of their SRB Banking Licence to enable such conversion and to provide a full range of S£ products.
Pensions Guarantee. Anyone in receipt of a pension that is paid in sterling and they reside in Scotland will be guaranteed the higher of the actual exchanged amount or the one to one S£ amount.