Here's some screenshot of the 2021 return for the same client:

The election was made. Assets were put input.

But yes. I'm sure the election was made. It's still shouldn't have 200% double declining balance method on AMT.

What I found in the instructions for the Form 6251 was this, which does seem to indicate that ADS lives aren't used for AMT anymore:

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Property placed in service after 1998. Use the same convention and recovery period used for the regular tax. For property other than section 1250 property, use the 150% declining balance method, switching to straight line the first tax year it gives a larger deduction. For section 1250 property, use the straight line method.

How Is the AMT Class Life Determined?
The class life used for the AMT isn’t necessarily the same as the recovery period used for the regular tax. The class lives for the AMT are listed in Rev. Proc. 87-56, 1987-2 C.B. 674, and in
Pub. 946, How To Depreciate Property. Use 12 years for any tangible personal property not assigned a class life.

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