Change in method of depreciation

Dear all,

If we are going to change the method of depreciation from WDV to SLM in FY 2016-17 as per AS 10 "Property, Plant and Equipment", such change is recognised as change in accounting estimate and accounted prospectively, then on what amount depreciation will be charged?

Whether the amount of depreciation for FY 2016-17 would be on opening value on 01.04.2016 or on original cost?

Regards.