Length of rental period when converting primary residence TO rental for 1031?

[Layla Savant]

Hello everyone! 

From what I've gathered, when converting a property acquired via a 1031 to a primary residence, one needs to be very careful to not trigger tax consequences by rkeeping the newly acquired property for at least 2-3 years as a rental. 

However, I'm not seeing much information about the reverse scenario - when a homeowner wants to convert his/her property to a rental with the intention of doing a 1031 exchange ASAP (say, to increase ROI by converting a SFH to a multi), what's the length of time the property needs to be rented for it to be considered an investment? 6 months? 1 year?

Thanks!