So, indeed, the "rapture" is scheduled to take place on May 21. That means that, on May 21 - as so many billboards and painted covered vans have been advertising diligently - the saints are going to disappear. I think the proper order is that the 'dead in Christ' get to rise first, then we who are alive and remain will be caught up to meet him in the air. That's the event that we are supposed to expect on May 21, based on the words of
I Thessalonians 4:16-18, which reads like this:
For the Lord himself, with a cry of command, with the archangel’s call and with the sound of God’s trumpet, will descend from heaven, and the dead in Christ will rise first. Then we who are alive, who are left, will be caught up in the clouds together with them to meet the Lord in the air; and so we will be with the Lord for ever. Therefore encourage one another with these words.
In the old days, the word that is translated 'to meet' (which is actually a noun - a meeting - not a verb) was the kind of language that signified going out to meet a dignitary that was coming on the highway. (This is how it used in the parable of the 10 Bridesmaids in Matthew 25.) The locals would get cleaned up and go out to meet the dignitary, then accompany him or her back to their humble abode with joy and thanksgiving. That is why the historic church read this passage as a description of the "second coming," not the "meet me half way." For some reason, the "rapture" proponents have turned this formula around to where Jesus 'comes,' and we 'meet him in the air' and then he takes us to his house, while suffering happens back in the old homestead.
So, on May 21, apparently, we're supposed to go to meet the 'coming' Christ, but he's not really coming. He's meeting us halfway and taking us to his house until he really comes later, so it's the "1.5 coming." But, I can't remember any of our Christian forebears talking about that. Can you?