So now we must MODIFY God's timing per your view?
2 Peter 3:8
8 But, beloved, be not ignorant of this one thing, that one day is with the Lord as a thousand years, and a thousand years as one day.
KJV
Must be a very real Truth there if Peter told us to not be ignorant of that.
One day is with The Lord as a thousand years.
That is His timing relation, not ours, and it is meant literally, for Apostle Peter wouldn't be commanding us to not be ignorant of that if he were just giving an expression.
You are totally missing the thrust. There it is absolutely nothing here to do with a future age, but time in the here-and-now. This text simply indicates the briefness of time with God. 2 Peter 3 does not in any way indicate a future earthly millennium kingdom anywhere in this reading. In fact, Peter is simply reminding the end-time scoffers that time is absolutely nothing to the king of glory; He ultimately sits outside of time in the realm of eternity. Time is but a blink to His infinite mind and to the eternal state. God is “from everlasting” (Habakkuk 1:12, Psalm 93:2). This isn't rocket science. It is simple, accurate and contextual.