Heat Pump Rebate and Inflation Reduction Act: Purchase in 2022, installed in 2023?

Hello TurboTax Team:

 

We plan to upgrade our heating and cooling with an energy efficient heat pump. Our local installer gave us a bid in October '22, but warned that the installation wouldn't be until March '23. My question is about the rebates and discounts that are a part of the IRA. If I sign a contract now in October so I can reserve my spot for installation in March '23, can I take advantage of the increased rebate? Or should I wait until January '23 to sign the contract. (If if matters, payment is due at the time of installation.) 

 

I imagine a lot of folks are going to want to do this work in the future, and we want the cooling more than the heating, so it's OK for us to wait a bit.

 

Does anyone understand the details of the IRA and timing of purchasing vs. installation?

 

Thank you!