Field help (DPM8) 

Help common to the single and mass processes for the account posting change.
This field displays the depreciation mode, potentially defined when applying the field association following an account posting change. Otherwise, the field is left blank.
It can be entered or modified only if the Process indicator has been activated for the plan. This mode should be authorised for the related company, plan and country.

The choice of the mode is submitted to the following restrictions:

The modification of the amortization mode can lead to the modification of the Depreciation start date of the plan and its loading, according to the setup carried out at the level of the Depreciation method, either with the First use date, or with the Purchase date, or with the Posting date.