How do you change the schedule CB for Mass state tax?

To get to the relevant section in TurboTax Online: 

1. Select Tax Home in the left pane
2. On the  Hi, let's keep working on your taxes! screen, select the dropdown on the right side of the State Taxes box, then select Continue, Pick up where you left off, or Review/Edit
3. If you land on a Massachusetts interview page, select Let's get started, Continue or other similar prompt.  Otherwise, in the left pane, select Prepare State, then proceed through the Massachusetts screens
4. When you get to the Massachusetts Credits page, late in the state TurboTax interview, select Update to the right of Senior circuit breaker credit
5. Make any changes necessary