Scars may widen, darken, or elevate following any trauma or surgery. The scar appearance largely depends upon the factors present during healing. In the case of breast scars, tension and swelling have a lot to do with the final outcome. If the breast is swollen, not supported, or too tight, the resulting scars will widen. If there are issues with healing or infection, the scars may also be quite wide. Correction with a scar revision is the usual treatment.
Appears you have a spreading hypertrophic scar issue. This could be related to the surgical techniques use and your scar genetics in concert. Best to seek a few in person second opinions..