KitchenAid Double Oven preheat differential

Oven Repair (including Ranges and Cooktops)
1

Hi all,

I have a KitchenAid Double Oven, model KEBS277SSS04.
The upper element died so I replaced it.
Here are two pics of the old elment:
element

element detail

Here is where I got the new element: https://www.amazon.com/dp/B0034IXCDW?psc=1&ref=ppx_yo2_dt_b_product_details

It heats up again but I noticed the upper oven takes about 9 minutes longer to heat up than the lower oven. When I start them at the same time, they stay neck and neck in the reported degrees(according to the panel) until about 320ish degrees, then the upper slows down and the lower keeps on heating up at the original pace. Is this normal? Should I check anything else? Replace the temp probe?

Thanks,
Joe