The easiest way of moving the monies over is to do a client payment and then a nominal receipt via the postings:
From the LAD desktop select the Postings 1, then the Payments tab.
In the drop down select the Client Ledger.
Fill in all the detail required and the value of the posting.
Select OK/Next.
Select the Receipts tab.
Select Nominal Ledger.
Put the write off nominal you require the monies to go back to in.
Put all the details in you require and select OK/Next.
Remember to do a transfer at the bank for the money between Client and Office account.