Many Believers will have a barn fire after the Rapture, not loss of salvation.

2Thess lesson #136; The doctrine of Eternal Security is factual and often misunderstood. As noted in Hebrews 6 and 1Corinthians 6 a Christain can refuse to grow spiritually. They may even remove themselves from the truth of scripture in what they believe and how they live, there will be repercussions yet not a LOSS OF SALVATION.