Was there a preadamic race
The word Yom is day. It is 24 hours in context. As this scripture shows: And the evening and the morning were the first day. Angels were created on the fifth day as living creatures as Ezekiel 1 and 10 explains them. Therefore, there is no fall prior to Genesis 3. Angels do not exist prior to the fifth day and mankind is created on the sixth day. After the fall, God states that there are two seeds from Eden. The seed of the serpent that will not call on the name of the Lord. There are those that are seed of the woman that refer to Christ coming that call on the name of the Lord. Men call on the name of the Lord from Seth.
Genesis 3:15 says,
And I will put enmity between thee and the woman, and between thy seed and her seed; it shall bruise thy head, and thou shalt bruise his heel.
The sons of God are those that call on the name of the Lord. The daughters of men are those that will not call on the name of the Lord that follow Satan. The giants are referring to mighty men of renown and their children were like them.
Genesis 6:4 says,
There were giants in the earth in those days; and also after that, when the sons of God came in unto the daughters of men, and they bare children to them, the same became mighty men which were of old, men of renown.
Hebrews 2 says at what time have I said to any of the Angels you are my sons. They are only ministering spirits. The sons of God that present themselves to the Lord and Satan came among them to accuse them. Zachariah shows Joshua accuse from Satan and God stating that Joshua is plucked from the fire.
There was no preadamic race. Anyone teaching this is teaching false teaching.