Thank you for helping problem solve this depreciation issue. In past years I didn't pay much attention to the depreciation calculations relying on TTX to do the math. I will amend 2017, 2018, & 2019 to reflect 100% Business Use. I understand that there is no positive gain to amend 2015 & 2016 due to the 3 year IRS limitation on amending a return. Can I use the 2020 TTX Premier to amend the other 3 years?
