I carefully explained this in God's permissive control. They are still fulfilling God's predestined plan even in their rebellion.
Which is then according to Gods will. However the scriptures tell us sin and disobedience is NOT according to Gods will.
Basically what you are saying is God made a predestined plan that people would sin, but He is not responsible for the sin in His own plans.
All the sin is by freewill, predestined, foreknown by God, and part of His overall plan. If not then He is not sovereign and not God.
Huh? If it is predestined and foreknown because He planned it all out then there is no such thing as freewill.
The scripture refers to the predestined elect as should be obvious because the Bible is clear that not all will be saved.
Total nonsense.
For therefore we both labour and suffer reproach, because we trust in the living God, who is the Saviour of all men, specially of those that believe. 11These things command and teach.
It is not His will that any of the elect perish so He allows time so that all of them will hear the effectual call and respond by receiving Christ. How many generations/centuries is that? All Peter is saying is this may take a long time so do not get discouraged or murmur against God.
Did Adam perish? Was he not a son of God?
Your understanding of predestination is in error and your understanding of the elect/firstfruits is in error.
God predestinated the church, not the individuals in the church. And the firstfuit's are but the promise of the whole harvest.