You would be placing in service a rental property as of the date it was available to be rented.  Then, you would be taking it out of service as a rental and changing it to your principal residence as of August 2020.  

There seems to be confusion in the note you sent as to how you could buy it in Feb 2020, rent it in May 2020 through the remainder of the year, yet, have you move in on August 2020?

I am assuming you actually bought the house in February 2019 and the tenant moved in May 2019 and lived there the remainder of the year and the first part of 2020 until August 2020, when you changed it from being a rental property and changed it into a principal residence.

Your dates seem skewed and directly contradict what you say.

I bought a house in Feb 2020.

Okay.

that I rented out in May 2020

So the house sat empty from Feb 2020 until May 2020? Did you live in that house for even one single day between the date you closed on the purchase, and the date you started renting it out? When did you start advertising it for rent?

for the remainder of the year.

So it was rented from May 2020 until "at least" Dec 31, 2020?

I moved into the house in August 2020.

Huh? How is this possible if you rented it out "for the remainder of the year." ?????

Definitely need some clarification here. Otherwise, any information provided to you on this is based on assumptions. Our assumptions will most likely be wrong too, meaning that the information provided will also be wrong.