You need to consider how very different things are today in terms of how God relates to us compared to how He did prior to 70 AD. The other HUGE difference is we no longer wait in Hades for redemption and restoration with God upon death. We go straight to heaven upon our physical death. The '"the restoration of all things" was our re-connection to God that was lost in the Garden.
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The resurrection occurred in 66 AD and was witnessed by Nero and recorded by two Roman historians.
Paul was already saying this [in the bold ^ ] was a fact when he penned 2 Corinthians [chpt 5], which, to me, indicates that they were not awaiting the events surrounding 70ad for this to begin being the case... and most scholars believe Corinthians was written in the mid-50s (so this "change" you are speaking of in the bold, did not delay clear to the events surrounding 70ad).
See example in the following quote by GotQuestions:
[quoting GotQuestions] "Date of Writing: The Book of 2 Corinthians was very likely written approximately A.D. 55-57.
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"Connections: Throughout his epistles, Paul frequently refers to the Mosaic law, comparing it with the surpassing greatness of the gospel of Jesus Christ and salvation by grace. In 2 Corinthians 3:4-11, Paul contrasts the Old Testament law with the new covenant of grace, referring to the law as that which “kills” while the Spirit gives life. The law is the “ministry of death, written and engraved on stone” (v. 7; Exodus 24:12) because it brings only the knowledge of sin and its condemnation. The glory of the law is that it reflects the glory of God, but the ministry of the Spirit is much more glorious than the ministry of the law, because it reflects His mercy, grace and love in providing Christ as the fulfillment of the law." [end quoting; bold and underline mine]
https://www.gotquestions.org/Book-of-2-Corinthians.html
I remain unconvinced of your viewpoint.
The '"the restoration of all things" was our re-connection to God that was lost in the Garden.
Acts 3:21 - "whom indeed it behooves heaven to receive until the times of restoration of all things of which God spoke by the mouth of His holy prophets from the age."