You may find the situation that you take delivery of an asset on a particular date, and the depreciation starts on that date, however because of a delayed trading account with your supplier (e.g. car finance), that the finance date is a few weeks later.
Therefore the lease start date needs to change from the first use date that is used for depreciation calculations.
In order to do this, you'll need to remove the lease from the Asset then add the lease as a separate asset and link the two together.
To achieve this, follow the steps below:
1) Remove the lease from the asset (from the menu item Actions > Remove lease)
2) Add a new asset, manually with the start date for the lease
3) Generate the payment schedule
4) At the bottom of that screen, change the Tax Depreciation to "Doesn't exist" and Accounts depreciation to "No depreciation", also manually edit "Amount capitalised to make this zero"
5) Once you have saved that lease, choose Actions > Add existing asset to lease and then select the asset to connect the lease and asset: