My parents received their family based green card in June 2016. From 2016 to 2019, they lived in US for 24 months without staying overseas for more than 6 months. However, due to COVID, their 2019 trip back home got stretched and they returned back to US after 2 years and 1 month. They did apply for SB-1 visa and were granted it before entering into US. After their return, they stayed for another year so they have total 35 months of US stay (with one long stay outside US). Technically they can apply for citizenship after 30 months of US stay and after 5 years. But I am not sure how their stay outside US for more than 2 years will impact their ability to apply for a citizenship. Any information on this will be appreciated. Thanks!