How do I enter prior to 2017 Acquisition debt on Turbotax, to figure my current deductible mortgage interest?

All mortgage debt used to buy build or improve your main home and secured by that home since October 1987 is home acquisition debt.  When you enter the form 1098 data, the date on the form 1098 box 3 shows the date of the current loan. Based on that date the limits will be applied. 

If and only if your mortgage interest deduction is limited due to the average loan balance exceeding one of the limits, you will be presented with a page that asks you to review the loan details.  

1. Select "Review"
2. Enter the end of year loan balance (actually asks for 1 January 2023)
3. Leave the date box blank
4. Continue
5. The next page will ask when you originally took out the loan
6. If one of the statements applies to you answer "Yes" and enter the date your home originally secured the loan (should be prior to the Dec 2017 date)