Legal to move into my 1031 exchange- Safe Harbor clarification- capital gains

[Rachael K.]

Hi, I was hoping to get some clarification on the Safe Harbor law.  We are considering moving into our 1031 property and making it our primary residence.  We have rented it out the past 3 years. What happens with the capital gains taxes if this is done ... do they just disappear forever or will I only ever need to pay them if I sell this house?  Is it possible to transfer this 1031 to another property of mine?