Bulk importing of Bonus Depreciation is available in 'Advanced Import Assets' - you'll see this option at the 'Set up your Tax Depreciation Methods' step:

For this to work correctly, it is recommended that assets in your import spreadsheet that should have Bonus Depreciation applied be given a different Tax Method to those that should not have Bonus Depreciation applied, so that you can differentiate between these during import.

For example, you might consider setting up tax methods in this way:

- GDS 200DB HY - Bonus Depreciation

- GDS 200DB HY - No Bonus

When importing you would be asked to map both of these methods, and you'd tick the 'Apply Bonus Depreciation' for the first method and leave it unticked for the second method.