Did OP get called to fix this bug and bill in half-hour increments for it? I was assuming the scenario where it's a hired developer doing their thing as part of their regular workday (they write "I noticed a glitch"), writing a new feature and noticing the problem as they look at what they made

In an expensive consultant scenario where this is the only thing they need to do that day for this customer, yeah sure if you can ask a computer to replace a whole billing cycle then that is cheaper, at least when ignoring the climate externalities that come due later (idk how to price that in)