Asset Depreciation for Principal and sub Assets

Hi all

Need your support.

Scenario:

I have a principal asset e.g, an Aircraft and 2500 Capital Spares that are associated with the life of an aircraft.

All are depreciated over 10 years life using STL.

All assets are evaluated every year by the independent evaluater,

Question

if the life of the principal asset is evaluated at 8th year to another 4 years (8+4) 12 years and same affect should be shown with the capital stores, how can I update the service life of Capital Spare?

Should it be one by one for all 2500 lines? or is there any auto process to take this affect?