Mass upload of Unplanned Depreciation

Hello All

we have recently tried to implement the Asset Impairment Functionality and the 'prior period adjustments' functionality ((Doc ID 271793.1). We applied 11 patches for impairment. But after a lots of testing, we came to know that Asset Impairment functionality doesn't allow the prior period adjustments . But the business needs to reduce the cost of the asset for nearly 400K+ assets.

I  would like to know

1) if there is any mass change for unplanned depreciation, so that a group of assets can have unplanned depreciation to reduce the cost of the asset?

2) I see there are restriction on the cost adjustments once the asset has unplanned depreciation, not sure if it impacts any futher cost adjustments made in future