It seems 390/389 alkaline button cells can power the mini-lathe’s DROs for about a year:

Given that the replacement cells all come from the same batch, they’re aging on the shelf as well as in the DROs.
Once again, I replaced both of them.
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It seems 390/389 alkaline button cells can power the mini-lathe’s DROs for about a year:

Given that the replacement cells all come from the same batch, they’re aging on the shelf as well as in the DROs.
Once again, I replaced both of them.