But according to Paul Benware Abraham died in 1990 BC
And the law was given a year after the exodus so that is 1445BC
1990 BC - 1445 BC = 545 years. 545 years does not match up with 430 years which you are citing from Galatians 3:17.
What paul is suggesting that this 430 year period of time falls somewhere between Abraham and the law. He's not implying that this 430 years covers the entire time span from Abraham to the Law.
You asked 'where do we stick the 400 yrs?' We should also ask, "where do we stick the 430 yrs?"
For example the 430 yrs may in fact have came before the 400 yrs.
Timeline of where the 430 yrs and the 400 yrs may fall:
Abraham --> Issac --> Joseph --> [? yrs] --> [430 years] --> [? yrs] --> [400 years] --> [Exodus and law given]
Note: [? yrs] may equal 0 or some other number
The focus would be on the number in that historically true parable. Forty is used to represent the time of testing throughout the bible . Adding zeros as multiples does not change the spiritual meaning hid in those parables.
For instance the lord starts out with fifty . Using the number
five to represent all who are redeemed. Moving down in incremates of ten to represent a unknown also used in increment one, ten. hundred and thousand to represent a unknown . Ten in the end of the matter represents all redeemed representing by the fifty in the beginning. .God does not bargain with men in that way. The spiritual understanding must be sought out.
And the Lord said, If I find in Sodom
fifty righteous within the city, then I will spare all the place for their sakes. And Abraham answered and said, Behold now, I have taken upon me to speak unto the Lord, which am but dust and ashes Peradventure there shall lack five of the fifty righteous: wilt thou destroy all the city for lack of five? And he said, If I find there forty and five, I will not destroy it.And he spake unto him yet again, and said, Peradventure there shall be
forty found there. And he said, I will not do it for forty's sake. And he said unto him, Oh let not the Lord be angry, and I will speak: Peradventure there shall
thirty be found there. And he said, I will not do it, if I find thirty there. And he said, Behold now, I have taken upon me to speak unto the Lord: Peradventure there shall be
twenty found there. And he said, I will not destroy it for twenty's sake. And he said, Oh let not the Lord be angry, and I will speak yet but this once: Peradventure ten shall be found there. And he said,
I will not destroy it for ten's sake.Genesis 18:26-30