Can I file 1040-X to fix K-1 carryover more than 3 years ago

[neiku]

I've owned 40% share of a partnership LLC during 2018-2024, which will be dissolved soon by the end of 2024.

Each year I got a K-1 with net loss. Since my actively participated hours were on the borderline of 500 hours, I thought the loss was passive loss and thus claimed it as a carryover for the years of 2018-2022. Recently a CPA reviewed my tax returns and told me the K-1s treated me as an active participation so I should claim it as active loss and use it to offset my ordinary income each year. The CPA would like to amend my tax returns for 2020-2022 but give up 2018-2019 because they are more than 3 years old.

My question is: Is there a way to amend 2018 and 2019 as well? For example, 
Net operating loss, or "realize" 2018-2023 carryovers to 2024 tax return? Thank you!

[tagteam]

Ask your CPA, as your CPA must have a rationale for not filing the 2018 and 2019 returns.