What do the codes mean in Box 12 of the estate Schedule K-1?

Alternative Minimum Tax Items
A: Adjustment for minimum tax purposes
B: AMT adjustment attributable to qualified dividends*
C: AMT adjustment attributable to net short-term capital gain*
D: AMT adjustment attributable to net long-term capital gain*
E: AMT adjustment attributable to unrecaptured section 1250 gain*
F: AMT adjustment attributable to 28% rate gain*
G: Accelerated depreciation *
H: Depletion *
I: Amortization *
J

* Not supported

See the Schedule K-1 (Form 1041) instructions  for more info about these codes.