I have never heard this idea before. What supports it?
Am I going to be accused of going off-topic if I answer this question?
Paul supports this in Acts 24:15 (YLT), "Having hope toward God, which they themselves also wait for, that
there is ABOUT TO BE a rising again of the dead, both of righteous and unrighteous." Paul was then addressing Felix after his trial dated around AD 60.
Paul again in 2 Timothy 4:1 (YLT), "I do fully testify, then before God, and the Lord Jesus Christ,
who is ABOUT TO JUDGE living and dead at his manifestation and his reign..." This was written to Timothy just before Paul's imminent martyrdom in AD 67, because Paul said "my departure is at hand" in 2 Timothy 4:6.
Christ Himself in Matthew 16:27-28 (KJV), "For the Son of man shall come in the glory of his Father with his angels; and then he shall reward every man according to his works. Verily I say unto you,
There be some standing here, which shall not taste of death, till they see the Son of man coming in his kingdom." Christ bodily-returned while some of those He was speaking to were still alive to see Him return to the Mount of Olives.
Daniel also supports this in his description of the bodily resurrection in Daniel 12:1-2 which he predicted would occur just after a great tribulation for Daniel's people would take place - an unprecedented tribulation which had never before happened since there was a nation. Those of Daniel's people who were "written in the book" (of life) would be "delivered" by being resurrected, including Daniel himself (as promised at the end of the 1,335 days.
Christ duplicated Daniel's prediction by His description of the "great tribulation" which was coming for Judea and Jerusalem (Matthew 24:21).
"IMMEDIATELY AFTER the tribulation of those days" Christ promised He would be "coming in the clouds of heaven with power and great glory,
to gather the elect from the four winds, from one end of heaven to the other." That's the second bodily resurrection event at Christ's second coming. All the patriarchs were included in that bodily resurrection, as well as every saint who had died from creation up until that point.
All of these texts and more throughout the scriptures testify that there was a first-century bodily resurrection event which took place in AD 70. This took place on that year's Pentecost Day, to be exact, according to the ending of the 1,335 days countdown, which started with those two events of Daniel 12:11 taking place in AD 66 when Jerusalem was surrounded and broken into by Cestius Gallus's Roman army.
We now await Christ's third coming in our future and the final bodily resurrection event for all of those saints who will have died since AD 70.