I'm a new Club treasurer. Previous Treasurer withdrew. When doing audit found Schwab cost basis doesn't agree with Bivio for several holdings due to the lot cost basis used by Schwab was not FIFO. Schwab was set to Tax Optimizer, not FIFO. Have changed Schwab to FIFO going forward and reconciled Bivio to the Schwab 1099 for 2023 tax year and filed 2023 taxes with everything agreeing. But we still have two holdings that have different cost basis in Schwab and Bivio because of partial sales in prior years in which the lots sold in Bivio are different that those shown in the historical Schwab 1099 (in years 2015, 2018 and 2019, but with no effect on any sales in 2023). Number of shares and proceeds of the sales in past years agree and also the currently held number of shares and value, just not the cost basis. Should I update those past sales in Bivio to the Schwab lot cost basis, or ask Schwab to update them in their records to what is in Bivio? (Schwab 1099 for 2018 and 2019 shows the
shares and dates acquried for lots sold in those years, but 1099 for 2015 doesn't, just has the dollars, not the lots.)
BTW, I find both Schwab and Bivio great to work with and love the connection between the two. It's much easier than I was led to believe...but just not sure the right way to fix this past error.