Two or more consecutive years equals Form 3115:
See https://www.irs.gov/publications/p946#en_US_2023_publink1000107385
Adoption of accounting method defined.
Generally, you adopt a method of accounting for depreciation by using a permissible method of determining depreciation when you file your first tax return, or by using the same impermissible method of determining depreciation in two or more consecutively filed tax returns.
