@jtax Much appreciation of your patient answer. When I switched to the Forms mode (never used that mode before), I realized that TT did already carry over that specific lot from previous 6251, so I don't need to adjust any more. After proceeding to the Deduction and Credits interview, here are what I found:
1. For 2023, my AMT is below regular tax, so I don't owe AMT, thus cannot use the AMT credit to offset new AMT. However, I did get ~$1300 credit to offset regular tax. You're correct that $3000 is the max you can use past AMT credit to offset regular tax (based one of the references you cited in the 1st reply). Since I sold other equities, my credit is reduced to $1300, for the reason I could not figure out.
2. TT did use the the difference between unrealized gain and the final gain ($8000-$38000=-$30000) as LT capital loss to offset my LT gain generated by other equity disposition.
3. It seems after above credit and adjustment, there is no more carry over for the specific lot, thus I may not be able to recover all the AMT credit I originally paid.
Anyway, I consider this question has been answered. Thanks again!
