Do you think with all the satellite technology that a fake return can be produced to fool those left behind on this coming Ascension Day?
If so, the rapture would be before Ascension Day.

Constance Cumby's book "A Planned Deception" talks about this using holographic images.
 

9: And when he had spoken these things, while they beheld, he was taken up; and a cloud received him out of their sight.
10: And while they looked steadfastly toward heaven as he went up, behold, two men stood by them in white apparel;
11: Which also said, Ye men of Galilee, why stand ye gazing up into heaven? this same Jesus, which is taken up from you into heaven, shall so come in like manner as ye have seen him go into heaven.
KJV Acts 1:9-11