Ridges in Tummy Tuck Scar - Will They Flatten Out?

Sometimes there can be a mound of tissue at either end of a tummy tuck incision. Some surgeons allow these to remain and settle over time. They will settle over several months. Some surgeons address these mounds at surgery by removing them resulting in a longer overall incision.
If the mounds were left and they settle/flatten then you avoided a longer incision. If they do not settle then the mounds can be removed usually under local anesthesia which results in an overall longer incision. The key is the body will be given the benefit of the doubt to correct this issue in hopes that you will avoid a more lengthy incision

It is nearly impossible to predict at 3 weeks what your long term results will be. There is no doubt that some areas that are currently firm will soften wtih time.

if you are referring to uneven skin edges along the scar line, these usually smooth out with time. If you are referring to residual loose skin in the lateral areas, this is usually referred to as a dog ear and sometimes needs surgical revision. The best thing to do is discuss this with your plastic surgeon.