Fay,
Thank you for your kind comments about my post.
Your question was whether Israel be given a 3 day warning about the impending Rapture or not. Personally, I don't think there will be any warning about the day or hour. I also don't think any calculation can determine it.
“Now concerning that day or hour no one knows—neither the angels in heaven nor the Son—except the Father. Watch! Be alert! For you don’t know when the time is coming. It is like a man on a journey, who left his house, gave authority to his slaves, gave each one his work, and commanded the doorkeeper to be alert. Therefore be alert, since you don’t know when the master of the house is coming—whether in the evening or at midnight or at the crowing of the rooster or early in the morning. Otherwise, he might come suddenly and find you sleeping. And what I say to you, I say to everyone: Be alert!” (Mark 13:32-37)
Blessings!
Jim