Schedule E - Fair rental days and Personal use days

[Dianne Figueroa]

Need help determining the fair rental days. 

Purchased a rental property on July 15, 2019 and it took 3 weeks (repairing and making improvements) to get it ready to list on the MLS for rent. The property was listed on August 13, 2019 and two weeks later the property was under contract for the tenants to move-in on September 1, 2019.

My question is do I start counting days as of July 15th as this property was purchased for the sole purpose of renting it out?  Or, do I use September 1st which was when the tenant moved in?

Thanks in advance!