SPX flow from Friday is indicating 4400 as the flip point for this short week. Key word, short week.
If 4400 holds, we could melt up to 4450 followed by 4475 then 4500. Now, 4500c and 4500p are both SHORT. So don't expect a break over. That being said, if 4400 breaks and we slide under, 4350 is the first target then 4300.
Good luck.