Taxpayer is required to pay this and all future payments electronically is "Your estimated tax or extension payment exceeds $20,000"

Or if CA tax liability exceeds 80k

In this case the liability is 23k which is less that the 80k but more that the first 20k rule

Since ProSeries checked that mandatory epay box on its own, I now assume the 20k rule applies to the annual estimate requirement and not just each individual estimate payment