How to avoid tax on Lumpsum social security payments SSA-1099

There is an article on SSA 1099 with lumpsum payment for 2025 that includes payment from 2024. Turbo Tax has input screens to add the lumpsum for 2025 along with previous year amounts that is shown as asterisk on SSA-1099. However, the article also mentions that the additional tax due to lumpsum payment for previous year can be avoided by apportioning prior year benefits to those previous years’ income (still without filing any amended returns). I need information on how to help client avoid the additional tax and steps. 

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