Capital Gains Exmptions

Hello,

So from what I have read, you are exempt from capital gains if your profit from sell of a home is 250,000 or less and you lived in the home for 2 years. My question is how does the IRS know where you lived?  Do they use your postal address or address on file with your employer?  I lived in my home for 1.6 years and due to covid, I came back to Texas last summer when I found out my parents were diagnosed with covid and unfortunately my mom didn't survive. 😞    Anyhow,   the house was empty from May thru Sept at which time I returned then rented it out for the winter season.  So technically I have not lived there for 2 years but I have owned the home for 2 years now and of those 2 years, 6 months were rentals.  So again is there some other type of exemption or do I need to live there for another 6 months and if so how does the IRS verify.  I'm assuming they would used either my new postal address or the state I file in.  Thanks in advance