Have all the phones (old and new) been capitalised as fixed assets? If they have, then yes you need to dispose of the old phones - Cr. Fixed Assets with the cost, Dr. Accumulated Depreciation in the balance sheet to reverse out the total depreciation charged. Usually you would then also Dr. bank with the proceeds and the balancing figure is profit or loss on disposal in the P&L.
And again, if the director has received the money personally, then rather than Dr. to the bank for the proceeds, just Dr. his loan account instead.
If they were not capitalised originally, then the process will be different.